SOS!! I485 REF deadline and marriage

What's the deadline for I-485 REF?
My friend got I485 for REF AND he is going to marry somebody recently in order to add her in the I-485.
He is afraid that there is no enough time to get the wedding done and add her in the pending I-485...
Is there any way to extend the I-485 REF? If not, once the REF deadline is missed, that will result in the denial of I-485 and he has to file EB2 again, right?

Thanks.