diff --git a/.github/workflows/upstream pretest.yaml b/.github/workflows/upstream pretest.yaml
index 6061a0b9..c7df5ca1 100644
--- a/.github/workflows/upstream pretest.yaml	
+++ b/.github/workflows/upstream pretest.yaml	
@@ -13,6 +13,11 @@ concurrency:
    group: ${{ github.workflow }}
    cancel-in-progress: false
 
+# TODO delete trivial subm-pretest before testing
+# - One last commit at a time
+# TODO find a way to hide upstream-only changes
+# - Store sha on the pretest side, not subm-pretest
+
 # There are 2 steps of adding new upstream commits:
 # 1. Add new commits from the PR merge ref (and possibly custom branch): to "pretest/$pr_num" in fork
 # 2. Add commit with submodule ref move + test changes, with this ref move: to "subm-pretest/$org_repo/$pr_num" in POCGL repo
@@ -366,8 +371,9 @@ jobs:
                     if (-not $?) { throw "git push failed" }
                     
                     Write-Host "Merging with ${fork_main_branch_name}:"
+                    $fork_pretest_old_sha = git rev-parse HEAD
                     $pr_merge_sha = git rev-parse remotes/0_official/pull/$pr_num/merge
-                    git merge $fork_main_branch_name --no-ff --commit -m @"
+                    git merge $fork_main_branch_name --no-ff -m @"
                     Merge $fork_main_branch_name into $fork_branch_name
                     meta.pr_merge_sha=$pr_merge_sha
                     "@
@@ -376,6 +382,14 @@ jobs:
                     if (-not $?) { throw "git push failed" }
                     
                     $fork_pretest_sha = git rev-parse HEAD
+                    if ($fork_pretest_sha -eq $fork_pretest_old_sha) {
+                        git commit -a --allow-empty -m @"
+                        Update pretest meta
+                        meta.pr_merge_sha=$pr_merge_sha
+                        "@
+                        $fork_pretest_sha = git rev-parse HEAD
+                    }
+                    
                     Pop-Location