diff --git a/.github/scripts/cron-calls-community.sh b/.github/scripts/cron-calls-community.sh
index 311bd4a67..0f89a8596 100644
--- a/.github/scripts/cron-calls-community.sh
+++ b/.github/scripts/cron-calls-community.sh
@@ -6,6 +6,12 @@ DRY_RUN="${DRY_RUN:-true}"
 ANCHOR_DATE="2025-11-12"
 MEETING_LINK="https://zoom-lfx.platform.linuxfoundation.org/meeting/92041330205?password=2f345bee-0c14-4dd5-9883-06fbc9c60581"
 CALENDAR_LINK="https://zoom-lfx.platform.linuxfoundation.org/meetings/hiero?view=week"
+MEETING_HOUR="${MEETING_HOUR:-14}"  # 14:00 UTC — change this to adjust the meeting time
+
+if ! [[ "$MEETING_HOUR" =~ ^[0-9]+$ ]] || [ "$MEETING_HOUR" -lt 0 ] || [ "$MEETING_HOUR" -gt 23 ]; then
+  echo "ERROR: MEETING_HOUR must be an integer between 0 and 23, got '$MEETING_HOUR'."
+  exit 1
+fi
 
 CANCELLED_DATES=(
   "2025-12-24"
@@ -63,15 +69,25 @@ if [ -z "$ISSUE_DATA" ] || [ "$ISSUE_DATA" = "[]" ]; then
   exit 0
 fi
 
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+TIME_UNTIL_MEETING=$(python3 "$SCRIPT_DIR/utils/compute-time-until-meeting.py" "$TODAY" "$MEETING_HOUR")
+
+if [ "$TIME_UNTIL_MEETING" = "has already started" ]; then
+  echo "Meeting has already started. Skipping reminder."
+  exit 0
+fi
+
+TIME_PHRASE="will begin in approximately $TIME_UNTIL_MEETING"
+
 COMMENT_BODY=$(cat <<EOF
 Hello, this is CommunityCallBot.
 
-This is a reminder that the Hiero Python SDK Community Call will begin in approximately 4 hours (14:00 UTC).
+This is a reminder that the Hiero Python SDK Community Call $TIME_PHRASE (${MEETING_HOUR}:00 UTC).
 
 The call is an open forum where contributors and users can discuss topics, raise issues, and influence the direction of the Python SDK.
 
 Details:
-- Time: 14:00 UTC
+- Time: ${MEETING_HOUR}:00 UTC
 - Join Link: [Zoom Meeting]($MEETING_LINK)
 
 Disclaimer: This is an automated reminder. Please verify the schedule [here]($CALENDAR_LINK) for any changes.
diff --git a/.github/scripts/cron-calls-office-hours.sh b/.github/scripts/cron-calls-office-hours.sh
index b536ad377..5cc1338b2 100644
--- a/.github/scripts/cron-calls-office-hours.sh
+++ b/.github/scripts/cron-calls-office-hours.sh
@@ -6,6 +6,12 @@ DRY_RUN="${DRY_RUN:-true}"
 ANCHOR_DATE="2025-12-03"
 MEETING_LINK="https://zoom-lfx.platform.linuxfoundation.org/meeting/99912667426?password=5b584a0e-1ed7-49d3-b2fc-dc5ddc888338"
 CALENDAR_LINK="https://zoom-lfx.platform.linuxfoundation.org/meetings/hiero?view=week"
+MEETING_HOUR="${MEETING_HOUR:-14}"  # 14:00 UTC — change this to adjust the meeting time
+
+if ! [[ "$MEETING_HOUR" =~ ^[0-9]+$ ]] || [ "$MEETING_HOUR" -lt 0 ] || [ "$MEETING_HOUR" -gt 23 ]; then
+  echo "ERROR: MEETING_HOUR must be an integer between 0 and 23, got '$MEETING_HOUR'."
+  exit 1
+fi
 
 CANCELLED_DATES=(
   "2025-12-31"
@@ -63,15 +69,25 @@ if [ -z "$PR_DATA" ] || [ "$PR_DATA" = "[]" ]; then
   exit 0
 fi
 
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+TIME_UNTIL_MEETING=$(python3 "$SCRIPT_DIR/utils/compute-time-until-meeting.py" "$TODAY" "$MEETING_HOUR")
+
+if [ "$TIME_UNTIL_MEETING" = "has already started" ]; then
+  echo "Meeting has already started. Skipping reminder."
+  exit 0
+fi
+
+TIME_PHRASE="will begin in approximately $TIME_UNTIL_MEETING"
+
 COMMENT_BODY=$(cat <<EOF
 Hello, this is the OfficeHourBot.
 
-This is a reminder that the Hiero Python SDK Office Hours are scheduled in approximately 4 hours (14:00 UTC).
+This is a reminder that the Hiero Python SDK Office Hours $TIME_PHRASE (${MEETING_HOUR}:00 UTC).
 
 This session provides an opportunity to ask questions regarding this Pull Request.
 
 Details:
-- Time: 14:00 UTC
+- Time: ${MEETING_HOUR}:00 UTC
 - Join Link: [Zoom Meeting]($MEETING_LINK)
 
 Disclaimer: This is an automated reminder. Please verify the schedule [here]($CALENDAR_LINK) for any changes.
diff --git a/.github/scripts/tests/test_compute_time_until_meeting.py b/.github/scripts/tests/test_compute_time_until_meeting.py
new file mode 100644
index 000000000..e75efb380
--- /dev/null
+++ b/.github/scripts/tests/test_compute_time_until_meeting.py
@@ -0,0 +1,211 @@
+"""Unit tests for compute-time-until-meeting.py helper.
+
+Run with:
+    python3 -m unittest .github/scripts/tests/test_compute_time_until_meeting.py -v
+
+Or from the tests directory:
+    python3 -m unittest test_compute_time_until_meeting -v
+"""
+
+from __future__ import annotations
+
+import os
+import sys
+import unittest
+from datetime import datetime, timedelta, timezone
+from importlib import import_module
+
+
+# Add the utils directory to sys.path so we can import the helper
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "utils"))
+
+# Import the module using importlib since the filename has hyphens
+_mod = import_module("compute-time-until-meeting")
+compute_time_until_meeting = _mod.compute_time_until_meeting
+_format_duration = _mod._format_duration
+_pluralize = _mod._pluralize
+_parse_mock_time = _mod._parse_mock_time
+
+
+class TestComputeTimeUntilMeeting(unittest.TestCase):
+    """Tests for the compute_time_until_meeting function."""
+
+    def test_standard_4_hours_before(self):
+        """Standard case: 10:00 run for 14:00 meeting = 4 hours."""
+        result = compute_time_until_meeting("today", 14, "10:00")
+        self.assertEqual(result, "4 hours")
+
+    def test_delayed_run_3h7m(self):
+        """Delayed run: 10:53 run for 14:00 meeting = 3 hours and 7 minutes."""
+        result = compute_time_until_meeting("today", 14, "10:53")
+        self.assertEqual(result, "3 hours and 7 minutes")
+
+    def test_just_minutes_remaining(self):
+        """Only minutes left: 13:45 run for 14:00 meeting = 15 minutes."""
+        result = compute_time_until_meeting("today", 14, "13:45")
+        self.assertEqual(result, "15 minutes")
+
+    def test_exact_whole_hours(self):
+        """Exact hours: 12:00 run for 14:00 meeting = 2 hours."""
+        result = compute_time_until_meeting("today", 14, "12:00")
+        self.assertEqual(result, "2 hours")
+
+    def test_past_meeting_time(self):
+        """Past meeting: 15:00 run for 14:00 meeting = has already started."""
+        result = compute_time_until_meeting("today", 14, "15:00")
+        self.assertEqual(result, "has already started")
+
+    def test_singular_hour(self):
+        """Singular: 13:00 run for 14:00 meeting = 1 hour (not '1 hours')."""
+        result = compute_time_until_meeting("today", 14, "13:00")
+        self.assertEqual(result, "1 hour")
+
+    def test_singular_minute(self):
+        """Singular: 12:59 run for 14:00 meeting = 1 hour and 1 minute."""
+        result = compute_time_until_meeting("today", 14, "12:59")
+        self.assertEqual(result, "1 hour and 1 minute")
+
+    def test_different_meeting_hour(self):
+        """Different hour: 08:30 run for 12:00 meeting = 3 hours and 30 minutes."""
+        result = compute_time_until_meeting("today", 12, "08:30")
+        self.assertEqual(result, "3 hours and 30 minutes")
+
+    def test_rounding_with_seconds(self):
+        """Seconds should ceil: 10:53:30 run for 14:00 = 3 hours and 7 minutes."""
+        result = compute_time_until_meeting("today", 14, "10:53:30")
+        self.assertEqual(result, "3 hours and 7 minutes")
+
+    def test_seconds_just_past_boundary(self):
+        """Just past minute: 13:00:01 run for 14:00 rounds up to 1 hour."""
+        result = compute_time_until_meeting("today", 14, "13:00:01")
+        self.assertEqual(result, "1 hour")
+
+    def test_utc_day_boundary(self):
+        """Cross-day: 23:00 run for 02:00 next day = 3 hours."""
+        tomorrow = (datetime.now(timezone.utc) + timedelta(days=1)).strftime("%Y-%m-%d")
+        result = compute_time_until_meeting(tomorrow, 2, "23:00")
+        self.assertEqual(result, "3 hours")
+
+    def test_same_day_morning_meeting_already_passed(self):
+        """Same-day early hour: 10:00 run with MEETING_HOUR=2 = has already started.
+
+        This is the key edge case that the old -12h rollover heuristic got wrong.
+        """
+        result = compute_time_until_meeting("today", 2, "10:00")
+        self.assertEqual(result, "has already started")
+
+    def test_explicit_date(self):
+        """Explicit date: passing a specific YYYY-MM-DD date works correctly."""
+        tomorrow = (datetime.now(timezone.utc) + timedelta(days=1)).strftime("%Y-%m-%d")
+        result = compute_time_until_meeting(tomorrow, 14, "10:00")
+        self.assertIn("hour", result)
+
+    def test_meeting_at_exact_time(self):
+        """Exact meeting time: 14:00 run for 14:00 meeting = has already started."""
+        result = compute_time_until_meeting("today", 14, "14:00")
+        self.assertEqual(result, "has already started")
+
+    def test_invalid_date_format(self):
+        """Invalid date format raises ValueError."""
+        with self.assertRaises(ValueError):
+            compute_time_until_meeting("not-a-date", 14, "10:00")
+
+    def test_midnight_meeting_hour_0(self):
+        """Edge of range: MEETING_HOUR=0, run at 22:00 yesterday = 2 hours."""
+        tomorrow = (datetime.now(timezone.utc) + timedelta(days=1)).strftime("%Y-%m-%d")
+        result = compute_time_until_meeting(tomorrow, 0, "22:00")
+        self.assertEqual(result, "2 hours")
+
+    def test_late_meeting_hour_23(self):
+        """Edge of range: MEETING_HOUR=23, run at 20:00 = 3 hours."""
+        result = compute_time_until_meeting("today", 23, "20:00")
+        self.assertEqual(result, "3 hours")
+
+    def test_one_minute_remaining(self):
+        """Edge: 13:59 run for 14:00 meeting = 1 minute."""
+        result = compute_time_until_meeting("today", 14, "13:59")
+        self.assertEqual(result, "1 minute")
+
+    def test_cli_invocation(self):
+        """CLI: calling via subprocess produces expected output."""
+        import subprocess
+
+        helper_path = os.path.join(os.path.dirname(__file__), "..", "utils", "compute-time-until-meeting.py")
+        result = subprocess.run(
+            ["python3", helper_path, "today", "14", "10:00"], capture_output=True, text=True, check=True
+        )
+        self.assertEqual(result.returncode, 0)
+        self.assertEqual(result.stdout.strip(), "4 hours")
+
+    def test_cli_missing_args(self):
+        """CLI: missing arguments should exit with error."""
+        import subprocess
+
+        helper_path = os.path.join(os.path.dirname(__file__), "..", "utils", "compute-time-until-meeting.py")
+        result = subprocess.run(["python3", helper_path], capture_output=True, text=True, check=False)
+        self.assertEqual(result.returncode, 1)
+
+
+class TestFormatDuration(unittest.TestCase):
+    """Tests for the _format_duration helper."""
+
+    def test_hours_and_minutes(self):
+        self.assertEqual(_format_duration(3, 7), "3 hours and 7 minutes")
+
+    def test_only_hours(self):
+        self.assertEqual(_format_duration(4, 0), "4 hours")
+
+    def test_only_minutes(self):
+        self.assertEqual(_format_duration(0, 15), "15 minutes")
+
+    def test_singular_hour(self):
+        self.assertEqual(_format_duration(1, 0), "1 hour")
+
+    def test_singular_minute(self):
+        self.assertEqual(_format_duration(0, 1), "1 minute")
+
+    def test_singular_both(self):
+        self.assertEqual(_format_duration(1, 1), "1 hour and 1 minute")
+
+
+class TestPluralize(unittest.TestCase):
+    """Tests for the _pluralize helper."""
+
+    def test_singular(self):
+        self.assertEqual(_pluralize(1, "hour"), "hour")
+
+    def test_plural(self):
+        self.assertEqual(_pluralize(2, "hour"), "hours")
+
+    def test_zero_is_plural(self):
+        self.assertEqual(_pluralize(0, "minute"), "minutes")
+
+
+class TestParseMockTime(unittest.TestCase):
+    """Tests for the _parse_mock_time helper."""
+
+    def test_valid_hh_mm(self):
+        self.assertEqual(_parse_mock_time("10:30"), (10, 30, 0))
+
+    def test_valid_hh_mm_ss(self):
+        self.assertEqual(_parse_mock_time("10:30:45"), (10, 30, 45))
+
+    def test_invalid_format(self):
+        with self.assertRaises(ValueError):
+            _parse_mock_time("10")
+
+    def test_non_numeric(self):
+        with self.assertRaises(ValueError):
+            _parse_mock_time("ab:cd")
+
+    def test_out_of_range_hour(self):
+        with self.assertRaises(ValueError):
+            _parse_mock_time("25:00")
+
+    def test_out_of_range_minute(self):
+        with self.assertRaises(ValueError):
+            _parse_mock_time("10:60")
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/.github/scripts/utils/compute-time-until-meeting.py b/.github/scripts/utils/compute-time-until-meeting.py
new file mode 100644
index 000000000..a0b86e19c
--- /dev/null
+++ b/.github/scripts/utils/compute-time-until-meeting.py
@@ -0,0 +1,112 @@
+"""Compute human-readable time remaining until a meeting.
+
+Usage:
+    python3 compute-time-until-meeting.py <MEETING_DATE> <MEETING_HOUR> [MOCK_TIME]
+
+Arguments:
+    MEETING_DATE  The date of the meeting in YYYY-MM-DD format, or 'today'
+    MEETING_HOUR  Meeting hour in UTC (0-23)
+    MOCK_TIME     Optional mock time in HH:MM or HH:MM:SS format (for testing)
+
+Output:
+    A human-readable string like "3 hours and 7 minutes" printed to stdout.
+"""
+
+from __future__ import annotations
+
+import sys
+from datetime import datetime, timezone
+from math import ceil
+
+
+def _parse_mock_time(mock_time):
+    """Parse a mock time string into (hour, minute, second) components."""
+    parts = mock_time.split(":")
+    if len(parts) not in (2, 3):
+        raise ValueError("MOCK_TIME must be in HH:MM or HH:MM:SS format.")
+    try:
+        hour = int(parts[0])
+        minute = int(parts[1])
+        second = int(parts[2]) if len(parts) == 3 else 0
+    except ValueError as exc:
+        raise ValueError("MOCK_TIME must contain only numeric components.") from exc
+
+    if not (0 <= hour <= 23 and 0 <= minute <= 59 and 0 <= second <= 59):
+        raise ValueError("MOCK_TIME values must be within valid UTC ranges.")
+    return hour, minute, second
+
+
+def _pluralize(value, singular):
+    """Return singular or plural form based on value."""
+    return singular if value == 1 else f"{singular}s"
+
+
+def _format_duration(hours, minutes):
+    """Format hours and minutes into a human-readable string."""
+    if hours > 0 and minutes > 0:
+        return f"{hours} {_pluralize(hours, 'hour')} and {minutes} {_pluralize(minutes, 'minute')}"
+    if hours > 0:
+        return f"{hours} {_pluralize(hours, 'hour')}"
+    return f"{minutes} {_pluralize(minutes, 'minute')}"
+
+
+def compute_time_until_meeting(meeting_date_str, meeting_hour, mock_time=None):
+    """Compute the human-readable time remaining until the meeting.
+
+    Args:
+        meeting_date_str: The meeting date as "YYYY-MM-DD" or "today".
+        meeting_hour: The meeting hour in UTC (0-23).
+        mock_time: Optional mock time string in "HH:MM" or "HH:MM:SS" format.
+
+    Returns:
+        A string like "3 hours and 7 minutes".
+    """
+    now = datetime.now(timezone.utc)
+
+    if mock_time is not None:
+        hour, minute, second = _parse_mock_time(mock_time)
+        now = now.replace(hour=hour, minute=minute, second=second, microsecond=0)
+
+    if meeting_date_str.lower() == "today":
+        meeting_date = now.date()
+    else:
+        try:
+            meeting_date = datetime.strptime(meeting_date_str, "%Y-%m-%d").date()
+        except ValueError as exc:
+            raise ValueError("MEETING_DATE must be in YYYY-MM-DD format or 'today'.") from exc
+
+    meeting = datetime(
+        year=meeting_date.year,
+        month=meeting_date.month,
+        day=meeting_date.day,
+        hour=meeting_hour,
+        minute=0,
+        second=0,
+        microsecond=0,
+        tzinfo=timezone.utc,
+    )
+
+    diff = meeting - now
+    if diff.total_seconds() <= 0:
+        return "has already started"
+
+    total_minutes = max(ceil(diff.total_seconds() / 60), 0)
+
+    return _format_duration(total_minutes // 60, total_minutes % 60)
+
+
+if __name__ == "__main__":
+    if len(sys.argv) < 3:
+        print("Usage: python3 compute-time-until-meeting.py <MEETING_DATE> <MEETING_HOUR> [MOCK_TIME]", file=sys.stderr)
+        sys.exit(1)
+
+    try:
+        meeting_date_str = sys.argv[1]
+        meeting_hour = int(sys.argv[2])
+        if not 0 <= meeting_hour <= 23:
+            raise ValueError("MEETING_HOUR must be an integer between 0 and 23.")
+        mock_time = sys.argv[3] if len(sys.argv) > 3 else None
+        print(compute_time_until_meeting(meeting_date_str, meeting_hour, mock_time))
+    except ValueError as exc:
+        print(f"ERROR: {exc}", file=sys.stderr)
+        sys.exit(1)