I'm sure other circuits will chime in, and if they differ with each other that makes it fairly certain the USSC will take on the cases. OTOH, if they all, ultimately, strike down Biden's reg, that makes it likely the USSC will let the strike-downs stand.
As I've posted before, this is a fight Biden & Krew should not have picked, as they are not likely even to win a Pyrrhic victory.