diff --git a/.github/workflows/steamify-iso.yml b/.github/workflows/steamify-iso.yml
index d4fb38f..7b292a3 100644
--- a/.github/workflows/steamify-iso.yml
+++ b/.github/workflows/steamify-iso.yml
@@ -39,7 +39,10 @@ jobs:
           fetch-depth: 0
 
       - name: Steamify on the ISO (its newest release)
-        run: ./steamify-prepare.sh
+        run: |
+          ./steamify-prepare.sh
+          # One moment for the ISO's label (profiledef.sh) and the release's name.
+          echo "STEAMIFY_BUILD_STAMP=$(date -u +%Y%m%d_%H%M)" >> "$GITHUB_ENV"
 
       - name: Build
         run: |
@@ -54,12 +57,12 @@ jobs:
         run: |
           iso="$(ls out/desktop/*.iso | head -n 1)"
           [ -f "$iso" ] || { echo "::error::no ISO in out/desktop"; exit 1; }
-          date="$(basename "$iso" | grep -oE '[0-9]{4}\.[0-9]{2}\.[0-9]{2}')"
           steamify="$(sed -n 's/^VERSION=//p' archiso/airootfs/usr/local/share/steamify/steamify.sh | head -n 1)"
           [ -n "$steamify" ] || { echo "::error::no Steamify version on the ISO"; exit 1; }
           api="${{ github.server_url }}/api/v1/repos/${{ github.repository }}"
           exists() { curl -fsS -o /dev/null -H "Authorization: token $TOKEN" "$api/releases/tags/$1"; }
-          stamp="$date-$(date -u +%H%M)"   # the ISO's date, the time of this run (UTC): every build its own name
+          b="$STEAMIFY_BUILD_STAMP"   # YYYYMMDD_HHMM (UTC), the same moment as the ISO's label
+          stamp="${b:0:4}.${b:4:2}.${b:6:2}-${b:9:4}"   # every build its own name
           if [ "${{ github.ref }}" = refs/heads/master ]; then
             tag="v$steamify-$stamp" prerelease=false name="CachyOS with Steamify Live ISO $steamify ($stamp UTC)"
           else
@@ -76,7 +79,7 @@ jobs:
           {
             echo "Built $(date -u '+%F %H:%M UTC') from \`$(git rev-parse --short HEAD)\` (${{ github.ref_name }}), with Steamify $steamify."
             echo
-            echo "SHA-256: \`$(cut -d' ' -f1 "$iso.sha256")\`"
+            echo "SHA-256: \`$(cut -d' ' -f1 "$iso.sha256")\`, label \`STEAMIFY_${steamify//./_}_$b\`"
             echo
             echo "$section"
           } > release-notes.md
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 25c32e2..f700044 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -32,7 +32,7 @@ Its version is the Steamify version on it plus the build date and time (a releas
 
 **Features:**
 
-* **ISO:** called `steamify-cachyos-<date>-x86_64.iso`; CachyOS Hello installs it like CachyOS's own
+* **ISO:** called `steamify-cachyos-<date>-x86_64.iso`, labelled after the Steamify version on it and the build time (`STEAMIFY_2_9_1_20260929_1432`, was CachyOS's `COS_<year><month>`); CachyOS Hello installs it like CachyOS's own
   release (the build date is kept in `/etc/steammachine-iso-build`)
 * **Installer (CachyOS - Steamify Installer):**
   * A Steamify page after the packages page: which Steam Machine parts to set up (rows from
diff --git a/archiso/profiledef.sh b/archiso/profiledef.sh
index a6be25b..2b72809 100644
--- a/archiso/profiledef.sh
+++ b/archiso/profiledef.sh
@@ -2,7 +2,14 @@
 # shellcheck disable=SC2034
 
 iso_name="steamify-cachyos"
-iso_label="COS_$(date --date="@${SOURCE_DATE_EPOCH:-$(date +%s)}" +%Y%m)"
+# The label follows the release name: the Steamify version on the ISO (steamify-prepare.sh put it there)
+# plus the build date and time, e.g. STEAMIFY_2_9_1_20260929_1432 (ISO 9660: at most 32 characters,
+# A-Z 0-9 _). STEAMIFY_BUILD_STAMP (YYYYMMDD_HHMM, UTC) from the release workflow, so both name the same
+# moment; built by hand, the time now.
+_steamify="$(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:-$(date -u --date="@${SOURCE_DATE_EPOCH:-$(date +%s)}" +%Y%m%d_%H%M)}"
+iso_label="STEAMIFY_${_steamify:+${_steamify//./_}_}${_stamp}"
+iso_label="${iso_label:0:32}"
 iso_publisher="CachyOS <https://cachyos.org>"
 iso_application="Steamify CachyOS Live (based on CachyOS)"
 iso_version="$(date --date="@${SOURCE_DATE_EPOCH:-$(date +%s)}" +%Y.%m.%d)"