AI am pre-baking cakes for a big cake this weekend but I am running out of freezer room! Will I be able to refrigerate them instead of freezing? I always wrap in wax paper and plastic wrap the freeze...

I also want to know if I can start filling and crumb coating on thursday night? The cakes are for saturday...

Freezing and refrigerating do not achieve the same end with cakes I don't think. Freezing can assist in moisture retention because of the ice crystals that are formed in the cake itself when frozen. You would not get that with refrigeration.

As for the Thursday timeline, that is when I fill and frost cakes for Saturday weddings all the time so that I can have Friday to fondant and decorate. As long as your cakes are moist to begin with and you get the frosting on and do not allow the bare cake to sit out long at all, you should be fine.