diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9da5ccd..353be86 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -5,7 +5,10 @@ on:
   pull_request:
   push:
     branches:
-    - master
+    - main
+  schedule:
+    # run Tuesday at noon UTC
+    - cron: '0 13 * * 2'
 
 jobs:
   base:
@@ -19,7 +22,7 @@ jobs:
           path: ~/Library/Caches/pip
         - os: windows-latest
           path: ~\AppData\Local\pip\Cache
-        python-version: [3.6, 3.9]
+        python-version: ['3.7', '3.10']
     runs-on: ${{ matrix.os }}
 
     steps:
@@ -53,7 +56,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.9]
+        python-version: ['3.10']
 
     steps:
     - name: Check out repository
@@ -81,7 +84,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.9]
+        python-version: ['3.10']
 
     steps:
     - name: Check out repository
diff --git a/doc/release_notes.rst b/doc/release_notes.rst
index 13df263..fe9bcbf 100644
--- a/doc/release_notes.rst
+++ b/doc/release_notes.rst
@@ -5,6 +5,11 @@ Release Notes
 0.2 series
 ..........
 
+0.2.5 (2021-07-30)
+------------------
+* remove unit assignment `dimensionless` from SBML creation. (#136)
+* remove checks for consistency of units. (#135)
+
 0.2.4 (2021-05-28)
 ------------------
 
diff --git a/yaml2sbml/version.py b/yaml2sbml/version.py
index ed0527d..08d694e 100644
--- a/yaml2sbml/version.py
+++ b/yaml2sbml/version.py
@@ -1,3 +1,3 @@
 """yaml2sbml version."""
 
-__version__ = '0.2.4'
+__version__ = '0.2.5'