The souls of everyone will "know" the way to salvation after death. We will all have a final choice.
I believe that's true for some--especially those who have earnestly sought God out of a sincere heart.
I don't believe that's so for all.
In any case, waiting until then is super hazardous.
We might say, eternally hazardous.
Particularly since The Bible doesn't clearly say such a thing is true.