One would think that all ballots from Maricopa would be disallowed, and the vote count recalculated.
But I won’t hold my breath.
A little quick, perhaps sloppy research tells me that Biden won AZ with a margin of about 10,500 votes.
In Maricopa, Trump got 980,494 and Biden got 1,027,269. That's a margin in Biden's favor of 47,225.
If all ballots from Maricopa are invalid, Biden loses the state by about 35,000 votes.