diff --git a/libs/FastSenseCompanion/NotificationCenterPane.m b/libs/FastSenseCompanion/NotificationCenterPane.m
index 05c2d935..4222708a 100644
--- a/libs/FastSenseCompanion/NotificationCenterPane.m
+++ b/libs/FastSenseCompanion/NotificationCenterPane.m
@@ -35,7 +35,7 @@
     end
 
     properties (SetAccess = private)
-        IsAttached  logical = false
+        IsAttached = false   % logical flag (no type-constraint syntax — Octave-incompatible)
     end
 
     properties (Access = private)
@@ -48,7 +48,7 @@
         hLastUpdateLbl_ = []           % "Updated: HH:MM:SS" label
         hPopoutBtn_     = []           % pop-out icon uibutton
         Companion_      = []           % FastSenseCompanion handle (or [])
-        LastGoodEvents_ = Event.empty  % last successfully-read unacked set (survives detach)
+        LastGoodEvents_ = []  % last successfully-read unacked set (survives detach)
         LastIds_        = {}           % cellstr of LastGoodEvents_ ids (diff key)
         Listeners_      = {}           % addlistener handles; deleted on teardown
         IsStale_        = false        % true when the last EventStore read failed
@@ -69,7 +69,7 @@
             end
             obj.ThemeStruct_    = themeStruct;
             obj.IsAttached      = false;
-            obj.LastGoodEvents_ = Event.empty;
+            obj.LastGoodEvents_ = [];
             obj.LastIds_        = {};
             obj.Listeners_      = {};
             obj.IsStale_        = false;
@@ -232,14 +232,14 @@ function refresh(obj, eventStore)
         %   (stale) marker; never clear the inbox and never uialert.
             if ~obj.IsAttached; return; end
             if isempty(eventStore) || ~isvalid(eventStore)
-                obj.LastGoodEvents_ = Event.empty;
+                obj.LastGoodEvents_ = [];
                 obj.LastIds_        = {};
                 obj.IsStale_        = false;
                 obj.applyFilterAndRender_();
                 obj.setUpdatedLabel_(datetime('now'), false);
                 return;
             end
-            allEvents = Event.empty;
+            allEvents = [];
             readOk = true;
             try
                 allEvents = eventStore.getEvents();
@@ -353,7 +353,13 @@ function applyFilterAndRender_(obj)
                     otherwise,    wanted = [];
                 end
                 if ~isempty(wanted)
-                    events = events([events.Severity] == wanted);
+                    % Explicit loop (Octave can't comma-list-expand [events.Severity]
+                    % over a classdef object array) — mirrors the text filter below.
+                    sevMask = false(1, numel(events));
+                    for i = 1:numel(events)
+                        sevMask(i) = (events(i).Severity == wanted);
+                    end
+                    events = events(sevMask);
                 end
             end
             % Free-text filter over SensorName + ThresholdLabel (case-insensitive).
@@ -640,7 +646,7 @@ function ackForTest_(obj, eventId)
         %   An event is unacked iff AckedAt is empty OR all-NaN (mirrors
         %   Event.computeDisplayState). Empty input returns an empty Event array.
             if isempty(allEvents)
-                evs = Event.empty;
+                evs = [];
                 return;
             end
             mask = false(1, numel(allEvents));
@@ -654,7 +660,13 @@ function ackForTest_(obj, eventId)
         function evs = sortNewestFirst_(events)
         %SORTNEWESTFIRST_ Order events by StartTime, newest first.
             if numel(events) > 1
-                [~, ord] = sort([events.StartTime], 'descend');
+                % Explicit loop (Octave can't comma-list-expand [events.StartTime]
+                % over a classdef object array).
+                starts = zeros(1, numel(events));
+                for i = 1:numel(events)
+                    starts(i) = events(i).StartTime;
+                end
+                [~, ord] = sort(starts, 'descend');
                 evs = events(ord);
             else
                 evs = events;
@@ -666,7 +678,12 @@ function ackForTest_(obj, eventId)
             if isempty(events)
                 s = 0;
             else
-                s = max([events.Severity]);
+                % Explicit loop (Octave can't comma-list-expand [events.Severity]).
+                sevs = zeros(1, numel(events));
+                for i = 1:numel(events)
+                    sevs(i) = events(i).Severity;
+                end
+                s = max(sevs);
             end
         end
 
@@ -675,7 +692,11 @@ function ackForTest_(obj, eventId)
             if isempty(events)
                 ids = {};
             else
-                ids = arrayfun(@(e) e.Id, events, 'UniformOutput', false);
+                % Explicit loop (Octave can't arrayfun over a classdef object array).
+                ids = cell(1, numel(events));
+                for i = 1:numel(events)
+                    ids{i} = events(i).Id;
+                end
             end
         end
 
diff --git a/tests/StubEventStore.m b/tests/StubEventStore.m
index 4bb2ce3f..38cc2b43 100644
--- a/tests/StubEventStore.m
+++ b/tests/StubEventStore.m
@@ -22,7 +22,7 @@
     %   See also EventStore, Event, NotificationCenterPane, CaptureNotificationService.
 
     properties
-        Events_     = Event.empty   % Event array; configure in test setup
+        Events_     = []            % Event array (configure in test setup); [] not Event.empty for Octave parity
         AckedIds_   = {}            % cellstr: each eventId passed to acknowledgeEvent, in call order
         ThrowOnAck_ = false         % when true, acknowledgeEvent throws EventStore:unknownEventId
         ThrowOnGet_ = false         % when true, getEvents throws (exercises the stale path)
diff --git a/tests/suite/TestFastSenseCompanionPlantLogToolbar.m b/tests/suite/TestFastSenseCompanionPlantLogToolbar.m
index f03f4a8a..2811eff2 100644
--- a/tests/suite/TestFastSenseCompanionPlantLogToolbar.m
+++ b/tests/suite/TestFastSenseCompanionPlantLogToolbar.m
@@ -114,19 +114,20 @@ function cleanupAll(testCase)
         end
 
         function g = findToolbarGrid_(testCase, c) %#ok<INUSL>
-            % After v3.1 Plant Log + v4.0 Wiki Browser merges, the
-            % Companion toolbar is a 1x9 grid:
-            %   {110, 110, 110, 130, 70, 90, 70, '1x', 36}
+            % After v3.1 Plant Log + v4.0 Wiki Browser + v4.0 Phase 1040
+            % notification bell, the Companion toolbar is a 1x10 grid:
+            %   {110, 110, 110, 130, 70, 90, 70, 70, '1x', 36}
             fig = c.getFigForTest_();
             grids = findobj(fig, 'Type', 'uigridlayout');
             g = [];
             for i = 1:numel(grids)
-                if numel(grids(i).ColumnWidth) == 9
+                if numel(grids(i).ColumnWidth) == 10
                     cw = grids(i).ColumnWidth;
                     if iscell(cw) && isequal(cw{1}, 110) && isequal(cw{2}, 110) && ...
                             isequal(cw{3}, 110) && isequal(cw{4}, 130) && ...
                             isequal(cw{5}, 70)  && isequal(cw{6}, 90)  && ...
-                            isequal(cw{7}, 70)  && isequal(cw{9}, 36)
+                            isequal(cw{7}, 70)  && isequal(cw{8}, 70)  && ...
+                            isequal(cw{10}, 36)
                         g = grids(i);
                         return;
                     end
@@ -139,22 +140,23 @@ function cleanupAll(testCase)
     methods (Test)
 
         function testToolbarGridIs1x5(testCase)
-            % v3.1 Plant Log + v4.0 Wiki Browser merged: toolbar grew from
-            % 1x4 to 1x9.
-            %   col 1 = Events     (110)
-            %   col 2 = Live       (110)
-            %   col 3 = Tags       (110, v4.0 quick task 260519-bs4)
-            %   col 4 = Plant Log  (130, v3.1 Phase 1033 PLOG-INT-03)
-            %   col 5 = Tile       ( 70, v4.0 S0Y-01)
-            %   col 6 = Close all  ( 90, v4.0 S0Y-02)
-            %   col 7 = Wiki       ( 70, v4.0 Phase 1034)
-            %   col 8 = flex spacer
-            %   col 9 = gear       ( 36)
+            % v3.1 Plant Log + v4.0 Wiki Browser + Phase 1040 bell: toolbar
+            % grew from 1x4 to 1x10.
+            %   col 1  = Events     (110)
+            %   col 2  = Live       (110)
+            %   col 3  = Tags       (110, v4.0 quick task 260519-bs4)
+            %   col 4  = Plant Log  (130, v3.1 Phase 1033 PLOG-INT-03)
+            %   col 5  = Tile       ( 70, v4.0 S0Y-01)
+            %   col 6  = Close all  ( 90, v4.0 S0Y-02)
+            %   col 7  = Wiki       ( 70, v4.0 Phase 1034)
+            %   col 8  = Bell       ( 70, v4.0 Phase 1040 notification center)
+            %   col 9  = flex spacer
+            %   col 10 = gear       ( 36)
             d1 = testCase.makeEngine_('A');
             c = testCase.makeCompanion_({d1});
             g = testCase.findToolbarGrid_(c);
             testCase.verifyNotEmpty(g, ...
-                'toolbar grid (1x8 with ColumnWidth {110 110 110 130 70 90 ''1x'' 36}) must exist');
+                'toolbar grid (1x10 with ColumnWidth {110 110 110 130 70 90 70 70 ''1x'' 36}) must exist');
             cw = g.ColumnWidth;
             testCase.verifyEqual(cw{1}, 110, 'ColumnWidth{1} (Events)');
             testCase.verifyEqual(cw{2}, 110, 'ColumnWidth{2} (Live)');
@@ -163,8 +165,9 @@ function testToolbarGridIs1x5(testCase)
             testCase.verifyEqual(cw{5}, 70,  'ColumnWidth{5} (Tile, v4.0)');
             testCase.verifyEqual(cw{6}, 90,  'ColumnWidth{6} (Close all, v4.0)');
             testCase.verifyEqual(cw{7}, 70,  'ColumnWidth{7} (Wiki, v4.0 Phase 1034)');
-            testCase.verifyEqual(cw{8}, '1x', 'ColumnWidth{8} flex spacer');
-            testCase.verifyEqual(cw{9}, 36,  'ColumnWidth{9} (gear)');
+            testCase.verifyEqual(cw{8}, 70,  'ColumnWidth{8} (Bell, v4.0 Phase 1040)');
+            testCase.verifyEqual(cw{9}, '1x', 'ColumnWidth{9} flex spacer');
+            testCase.verifyEqual(cw{10}, 36, 'ColumnWidth{10} (gear)');
         end
 
         function testPlantLogButtonExists(testCase)
@@ -211,13 +214,13 @@ function testPlantLogButtonDisabledWithoutDashboards(testCase)
         end
 
         function testSettingsButtonMovedToCol5(testCase)
-            % After v3.1 + v4.0 merge, gear lives at col 8 (1x8 grid).
+            % After v3.1 + v4.0 + Phase 1040 bell, gear lives at col 10 (1x10 grid).
             d1 = testCase.makeEngine_('A');
             c = testCase.makeCompanion_({d1});
             gear = findobj(c.getFigForTest_(), 'Tooltip', 'Companion settings');
             testCase.verifyNotEmpty(gear);
-            testCase.verifyEqual(gear.Layout.Column, 9, ...
-                'settings gear must be at col 9 (1x9 grid post-v3.1+Wiki-Browser merge)');
+            testCase.verifyEqual(gear.Layout.Column, 10, ...
+                'settings gear must be at col 10 (1x10 grid post-Phase-1040 bell)');
         end
 
         function testFindObjResolvesViaTag(testCase)
diff --git a/tests/test_notification_center_pane.m b/tests/test_notification_center_pane.m
index 2ff007ea..c00750f2 100644
--- a/tests/test_notification_center_pane.m
+++ b/tests/test_notification_center_pane.m
@@ -43,7 +43,7 @@ function test_notification_center_pane()
 
     % 4. maxSeverity_.
     n = n + 1; check(NotificationCenterPane.maxSeverity_([e1 e2]) == 3, 'maxSeverity_([3 2]) should be 3');
-    n = n + 1; check(NotificationCenterPane.maxSeverity_(Event.empty) == 0, 'maxSeverity_(empty) should be 0');
+    n = n + 1; check(NotificationCenterPane.maxSeverity_([]) == 0, 'maxSeverity_(empty) should be 0');
 
     % 5. diffIds_ — order-insensitive set comparison.
     n = n + 1; check(~NotificationCenterPane.diffIds_({'a', 'b'}, {'b', 'a'}), ...