diff --git a/ct/semaphore.sh b/ct/semaphore.sh
index 7ac50de3f..9b2d48556 100644
--- a/ct/semaphore.sh
+++ b/ct/semaphore.sh
@@ -32,42 +32,61 @@ function update_script() {
     exit
   fi
 
-  if check_for_gh_release "semaphore" "semaphoreui/semaphore"; then
-    if [[ -f /opt/semaphore/semaphore_db.bolt ]]; then
-      msg_warn "WARNING: Due to bugs with BoltDB database, update script will move your application"
-      msg_warn "to use SQLite database instead. Make sure you have a backup of your data!"
-      echo ""
-      read -r -p "${TAB3}Do you want to continue? (y/N): " CONFIRM
-      if [[ ! "$CONFIRM" =~ ^[Yy]$ ]]; then
-        exit 0
-      else
-        msg_info "Moving from BoltDB to SQLite"
-        sed -i \
-          -e 's|"bolt": {|"sqlite": {|' \
-          -e 's|/semaphore_db.bolt"|/database.sqlite"|' \
-          -e '/semaphore_db.bolt/d' \
-          -e '/"dialect"/d' \
-          -e '/^  },$/a\  "dialect": "sqlite",' \
-          /opt/semaphore/config.json
-        msg_ok "Moved from BoltDB to SQLite"
-      fi
+  # Outside the release check on purpose: a container left behind by the old
+  # order already carries the newest version, so the check would skip it.
+  local migrated=0
+  if [[ -f /opt/semaphore/semaphore_db.bolt ]]; then
+    msg_warn "WARNING: Due to bugs with BoltDB database, update script will move your application"
+    msg_warn "to use SQLite database instead. Make sure you have a backup of your data!"
+    echo ""
+    read -r -p "${TAB3}Do you want to continue? (y/N): " CONFIRM
+    if [[ ! "$CONFIRM" =~ ^[Yy]$ ]]; then
+      exit 0
     fi
 
     msg_info "Stopping Service"
     systemctl stop semaphore
     msg_ok "Stopped Service"
 
-    fetch_and_deploy_gh_release "semaphore" "semaphoreui/semaphore" "binary" "latest" "/opt/semaphore" "semaphore_*_linux_$(arch_resolve).deb"
+    msg_info "Moving from BoltDB to SQLite"
+    sed -i \
+      -e 's|"bolt": {|"sqlite": {|' \
+      -e 's|/semaphore_db.bolt"|/database.sqlite"|' \
+      -e '/semaphore_db.bolt/d' \
+      -e '/"dialect"/d' \
+      -e '/^  },$/a\  "dialect": "sqlite",' \
+      /opt/semaphore/config.json
+    msg_ok "Moved from BoltDB to SQLite"
 
-    if [[ -f /opt/semaphore/semaphore_db.bolt ]]; then
-      $STD semaphore migrate --from-boltdb /opt/semaphore/semaphore_db.bolt --config /opt/semaphore/config.json
-      rm -f /opt/semaphore/semaphore_db.bolt
+    # 2.19 dropped BoltDB along with the migration flag, so this has to run on
+    # the last release that still has it.
+    fetch_and_deploy_gh_release "semaphore" "semaphoreui/semaphore" "binary" "v2.18.30" "/opt/semaphore" "semaphore_*_linux_$(arch_resolve).deb"
+
+    msg_info "Migrating BoltDB to SQLite"
+    if ! $STD semaphore migrate --from-boltdb /opt/semaphore/semaphore_db.bolt --config /opt/semaphore/config.json; then
+      msg_error "Migration failed - semaphore_db.bolt was kept, run the update again to retry"
+      exit 1
     fi
+    rm -f /opt/semaphore/semaphore_db.bolt
+    msg_ok "Migrated BoltDB to SQLite"
+    migrated=1
+  fi
+
+  if check_for_gh_release "semaphore" "semaphoreui/semaphore"; then
+    msg_info "Stopping Service"
+    systemctl stop semaphore
+    msg_ok "Stopped Service"
+
+    fetch_and_deploy_gh_release "semaphore" "semaphoreui/semaphore" "binary" "latest" "/opt/semaphore" "semaphore_*_linux_$(arch_resolve).deb"
 
     msg_info "Starting Service"
     systemctl start semaphore
     msg_ok "Started Service"
     msg_ok "Updated successfully!"
+  elif ((migrated)); then
+    msg_info "Starting Service"
+    systemctl start semaphore
+    msg_ok "Started Service"
   fi
   exit
 }