Can't remove a post from Gallery if reviewed by a moderator for any reason

I had a post reviewed by a moderator (a wrong check on "vendor ads" being marked ON).

I wanted to de-check the "add to Gallery" flag and remove the entry from the Gallery, but that wasn't possible because "the post has been reviewed by a moderator" so it could not be edited anymore.

The only remedy was to delete and re-post with the right "vendor ads" mark, but of course all the favorites went lost.