diff --git a/.github/workflows/test_sitl_copter.yml b/.github/workflows/test_sitl_copter.yml
index 3bc3eba85675..f07557611b5f 100644
--- a/.github/workflows/test_sitl_copter.yml
+++ b/.github/workflows/test_sitl_copter.yml
@@ -1,84 +1,10 @@
 name: test copter
 
 on:
-  push:
-    branches: ['**']  # excludes tag pushes
-    paths-ignore:
-      # remove other vehicles
-      - 'AntennaTracker/**'
-      - 'ArduPlane/**'
-      - 'ArduSub/**'
-      - 'Blimp/**'
-      - 'Rover/**'
-      # remove non SITL HAL
-      - 'libraries/AP_HAL_ChibiOS/**'
-      - 'libraries/AP_HAL_ESP32/**'
-      - 'libraries/AP_HAL_QURT/**'
-      # remove non SITL directories
-      - 'Tools/AP_Bootloader/**'
-      - 'Tools/AP_Periph/**'
-      - 'Tools/bootloaders/**'
-      - 'Tools/CHDK-Script/**'
-      - 'Tools/CodeStyle/**'
-      - 'Tools/completion/**'
-      - 'Tools/CPUInfo/**'
-      - 'Tools/debug/**'
-      - 'Tools/environment_install/**'
-      - 'Tools/FilterTestTool/**'
-      - 'Tools/Frame_params/**'
-      - 'Tools/geotag/**'
-      - 'Tools/GIT_Test/**'
-      - 'Tools/gittools/**'
-      - 'Tools/Hello/**'
-      - 'Tools/IO_Firmware/**'
-      - 'Tools/Linux_HAL_Essentials/**'
-      - 'Tools/Pozyx/**'
-      - 'Tools/PrintVersion.py'
-      - 'Tools/simulink/**'
-      - 'Tools/UDP_Proxy/**'
-      - 'Tools/vagrant/**'
-      - 'Tools/Vicon/**'
-      # Discard python file from Tools/scripts as not used
-      - 'Tools/scripts/**.py'
-      - 'Tools/scripts/build_sizes/**'
-      - 'Tools/scripts/build_tests/**'
-      - 'Tools/scripts/CAN/**'
-      - 'Tools/scripts/signing/**'
-      # Remove other vehicles autotest
-      - 'Tools/autotest/antennatracker.py'
-      - 'Tools/autotest/arduplane.py'
-      - 'Tools/autotest/ardusub.py'
-      - 'Tools/autotest/balancebot.py'
-      - 'Tools/autotest/location.txt'
-      - 'Tools/autotest/quadplane.py'
-      - 'Tools/autotest/rover.py'
-      - 'Tools/autotest/sailboat.py'
-      - 'Tools/autotest/swarminit.txt'
-      # Remove markdown files as irrelevant
-      - '**.md'
-      # Remove dotfile at root directory
-      - './.dir-locals.el'
-      - './.dockerignore'
-      - './.editorconfig'
-      - './.flake8'
-      - './.gitattributes'
-      - './.github'
-      - './.gitignore'
-      - './.pre-commit-config.yaml'
-      - './.pydevproject'
-      - './.valgrind-suppressions'
-      - './.valgrindrc'
-      - 'Dockerfile'
-      - 'Vagrantfile'
-      - 'Makefile'
-      # Remove some directories check
-      - '.vscode/**'
-      - '.github/ISSUE_TEMPLATE/**'
-      # Remove change on other workflows
-      - '.github/workflows/test_environment.yml'
-
-
+  # Matternet: no push trigger; the full Copter suite runs on pull requests
+  # into mttr-* branches, nightly on the default branch, and on demand.
   pull_request:
+    branches: ['mttr-*']
     paths-ignore:
       # remove other vehicles
       - 'AntennaTracker/**'
@@ -154,6 +80,8 @@ on:
       # Remove change on other workflows
       - '.github/workflows/test_environment.yml'
 
+  schedule:
+    - cron: '0 10 * * *'  # daily 02:00 Pacific (standard time)
   workflow_dispatch:
 
 concurrency: