Tell them that the salt is eating everything under your rig and for them to watch for the brown suited Santa bearing gifts. . Seriously though I have looked at RVs in Michigan that were owned by people who left after Christmas and the rust was terrible. It's not an in depth study but an RV has nothing as far as rust protection compared to our modern vehicles.
We leave mich in the early fall and make it a smooth transition from summer to a warmish winter.
We only have so much time left to enjoy our years. Maybe they could fly down and party with you where its warmer.