in src/main/java/com/googlesource/gerrit/plugins/refprotection/BackupRef.java [192:201]
static String getTimestampBranch(String refName) {
if (refName.startsWith(R_HEADS) || refName.startsWith(R_TAGS)) {
return String.format(
"%s-%s",
R_BACKUPS + refName.replaceFirst(R_REFS, ""),
new SimpleDateFormat("yyyyMMdd-HHmmss").format(new Date()));
}
return refName;
}