Warning: Slight Obscure Appellate Procedural Questions Ahead
Litigants sometimes file writ petitions in the Court of Appeal to seek review of grievous but nonappealable orders that come down prior to a judgment. If the writ petition is summarily denied (as they usually are), you may need to be prepared to argue that the denial has precedential effect in your case. Or, you may need to be prepared to argue that, no, in fact, it doesn't.
The recent decision in Ventura Cnty. Deputy Sheriffs' Ass'n v. Cnty. of Ventura (D2d6 Mar. 3, 2021) No. B300006, on the one hand, and prior cases on the other hand, should give you a start on either side of that split.