I am making my grandson's wedding cake and they live 9 hrs away from me. I am going to make the 4 tiered upside down cake at home and freeze it as I will be leaving early and can't make the cake until 2 days prior to the wedding.
Can someone please help me on how to wrap the cake properly as we are driving and want to keep it frozen.

I'll be honest, I don't see the need to keep them frozen in transport.

I have a "one freeze" rule.

In this case, I'd travel with the freshly baked & cooled cakes, carefully boxed and then wrapped in 2 layers of saran and a layer of foil. On arrival, I'd then freeze them, still wrapped. I'd take them out of the freezer, open the wrapping, and let them defrost most of the way before splitting & then filling. I'd crumb coat them, let them settle, and then decorate.

If you want to split & fill them before driving, obviously using a non-perishable filling, then I'd freeze the whole layers, defrost most of the way, split & fill, crumb coat, box, wrap in saran & foil, and then finish decorating on arrival.

Rae