More info please
What system are you using? I am not clear by what you mean by "where a dealer Blackjack is not a standoff against a 21"
Are you saying that the dealer looks for the blackjack after the hands are played out? Therefore the player can draw to 21 and this may or may not (may not in your case) "push" with the dealer.
Please be more clear in your posts. I understand if English is not your native language.