diff --git a/.github/workflows/iso-release.yml b/.github/workflows/iso-release.yml
index 6444144..c81fcea 100644
--- a/.github/workflows/iso-release.yml
+++ b/.github/workflows/iso-release.yml
@@ -3,7 +3,7 @@
 # builds the ISO on that tag and attaches it to its own release for it (steamify-iso.yml). The ISO lives there:
 # GitHub releases take at most 2 GB per file, the ISO is bigger, and a release on the mirror only survives its
 # syncs when its tag comes from here.
-# Name: the Steamify version the ISO gets (its newest release) plus the time (Dutch time, Europe/Amsterdam):
+# Name: the Steamify version the ISO gets (its newest release) plus the time (UTC, GitHub's clock when the release starts):
 # master releases v<steamify>-<YYYY.MM.DD>-<HHMM>, feat/steamify a pre-release v<steamify>-dev.<...>.
 name: Steamify ISO release (tag)
 
@@ -32,11 +32,11 @@ jobs:
         run: |
           steamify="$(gh release view -R theupriser/steamify-cachyos --json tagName -q .tagName)"
           steamify="${steamify#v}"
-          stamp="$(TZ=Europe/Amsterdam date +%Y.%m.%d-%H%M)"
+          stamp="$(date -u +%Y.%m.%d-%H%M)"
           if [ "${{ github.ref }}" = refs/heads/master ]; then
-            tag="v$steamify-$stamp" pre="" name="CachyOS with Steamify Live ISO $steamify ($stamp)"
+            tag="v$steamify-$stamp" pre="" name="CachyOS with Steamify Live ISO $steamify ($stamp UTC)"
           else
-            tag="v$steamify-dev.$stamp" pre="--prerelease" name="CachyOS with Steamify Live ISO $steamify (test build $stamp)"
+            tag="v$steamify-dev.$stamp" pre="--prerelease" name="CachyOS with Steamify Live ISO $steamify (test build $stamp UTC)"
           fi
           # The ISO's file on the mirror is named after the tag (steamify-iso.yml, profiledef.sh), so its
           # download link is known now.
diff --git a/.github/workflows/steamify-iso.yml b/.github/workflows/steamify-iso.yml
index ecd7f38..9fe1f1f 100644
--- a/.github/workflows/steamify-iso.yml
+++ b/.github/workflows/steamify-iso.yml
@@ -46,7 +46,7 @@ jobs:
           m=("${BASH_REMATCH[@]}")
           {
             echo "STEAMIFY_VERSION=${m[1]}"
-            # One moment for the ISO's label (profiledef.sh) and the release's name: the tag's (Dutch time).
+            # One moment for the ISO's label (profiledef.sh) and the release's name: the tag's (UTC).
             echo "STEAMIFY_BUILD_STAMP=${m[3]}${m[4]}${m[5]}_${m[6]}"
             echo "ISO_PRERELEASE=$([ -n "${m[2]}" ] && echo true || echo false)"
             # The ISO's file name: the tag without its v (profiledef.sh).
@@ -72,9 +72,9 @@ jobs:
           tag="${{ github.ref_name }}" b="$STEAMIFY_BUILD_STAMP"
           stamp="${b:0:4}.${b:4:2}.${b:6:2}-${b:9:4}"
           if [ "$ISO_PRERELEASE" = true ]; then
-            name="CachyOS with Steamify Live ISO $STEAMIFY_VERSION (test build $stamp)"
+            name="CachyOS with Steamify Live ISO $STEAMIFY_VERSION (test build $stamp UTC)"
           else
-            name="CachyOS with Steamify Live ISO $STEAMIFY_VERSION ($stamp)"
+            name="CachyOS with Steamify Live ISO $STEAMIFY_VERSION ($stamp UTC)"
           fi
           # Never overwritten: a release for this tag that already has the ISO is left alone.
           api="${{ github.server_url }}/api/v1/repos/${{ github.repository }}"
diff --git a/CHANGELOG.md b/CHANGELOG.md
index da103b5..eb14f25 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -28,7 +28,7 @@
 
 ## CachyOS with Steamify Live ISO
 CachyOS 26.08 with Steamify built in: install CachyOS and turn the PC into a Steam Machine in one go.
-Its version is the Steamify version on it plus the build date and time (Dutch time; a release on `master` is `v<Steamify version>-<date>-<HHMM>`, e.g. `v2.9.3-2026.09.29-2205`). A new Steamify release starts one (a test build for now); by hand: Run workflow on "Steamify ISO release (tag)".
+Its version is the Steamify version on it plus the build date and time (UTC, when the release starts on GitHub; a release on `master` is `v<Steamify version>-<date>-<HHMM>`, e.g. `v2.9.3-2026.09.29-2015`). A new Steamify release starts one (a test build for now); by hand: Run workflow on "Steamify ISO release (tag)".
 Releases: GitHub creates the tag and a release with the notes; the ISO itself (over GitHub's 2 GB limit) is built on the Gitea mirror and attached to its release for that tag (git.upriser.nl).
 
 **Features:**
diff --git a/archiso/profiledef.sh b/archiso/profiledef.sh
index 63029c6..d4fb74f 100644
--- a/archiso/profiledef.sh
+++ b/archiso/profiledef.sh
@@ -4,10 +4,10 @@
 iso_name="steamify-cachyos"
 # The label follows the release name: the Steamify version on the ISO (steamify-prepare.sh put it there)
 # plus the build date and time, e.g. STEAMIFY_2_9_1_20260929_1432 (ISO 9660: at most 32 characters,
-# A-Z 0-9 _). STEAMIFY_BUILD_STAMP (YYYYMMDD_HHMM, Dutch time) from the release workflow, so both name the
-# same moment; built by hand, the time now (Europe/Amsterdam).
+# A-Z 0-9 _). STEAMIFY_BUILD_STAMP (YYYYMMDD_HHMM, UTC) from the release workflow, so both name the same
+# moment; built by hand, the time now (UTC).
 _steamify="$(sed -n 's/^VERSION=//p' "${BASH_SOURCE[0]%/*}/airootfs/usr/local/share/steamify/steamify.sh" 2>/dev/null | head -n 1)"
-_stamp="${STEAMIFY_BUILD_STAMP:-$(TZ=Europe/Amsterdam date --date="@${SOURCE_DATE_EPOCH:-$(date +%s)}" +%Y%m%d_%H%M)}"
+_stamp="${STEAMIFY_BUILD_STAMP:-$(date -u --date="@${SOURCE_DATE_EPOCH:-$(date +%s)}" +%Y%m%d_%H%M)}"
 iso_label="STEAMIFY_${_steamify:+${_steamify//./_}_}${_stamp}"
 iso_label="${iso_label:0:32}"
 iso_publisher="CachyOS <https://cachyos.org>"