The solution changed a little bit, so your code should probably look like this:
if ($reviewStage) {
$submissionFile->setName($submissionFile->_generateName(true), AppLocale::getPrimaryLocale());
} else {
if ($isUpload || !$submissionFile->getName(AppLocale::getPrimaryLocale())) {
$submissionFile->setName($submissionFile->_generateName(), AppLocale::getPrimaryLocale());
}
}
i.e. with one more if clause…
Best,
Bozana