Honestly, seems like everyone and every manufacturer has a different recommended way of doing it.
Not sure if any one way is better than any other, but I've always winterized the plumbing in mine as if I might want to use it again, within an hour after I finish winterizing it.
- To start, I dump/drain all 3 tanks and the water heater, and leave the valves/drains/toilet holes open to the air for a few days afterwards, to let things evaporate, sublimate, or just dry out even more.
- Once the tanks and water heater are mostly drained and empty, I open every faucet and tap and prop open the toilet flush levers (or just hold it open) and run the water pump for 10-20 minutes or so to empty it out (they're designed to self prime and run dry for a while) and help to push water out of the rest of the plumbing tubing. This should pretty much empty the lines of any remaining water. The longer you leave everything open to the air, the drier your system will get.
- I don't use RV AF, except in the toilet and sink drains, to protect the traps, and lubricate the valves. Close the dump valves first, of course. At this point I'm pretty much dry in the plumbing, except for a few drops here and there.
- After a few more days, I might close the rest of the taps and faucets, on the outside and inside, but this is optional, and can probably wait until you're ready to use the system again. Maybe just close the outside shower taps and drains to keep critters out.
- This method has been used for 6 years now and I've never had a problem. I also don't have to deal with RVAF in my fresh water. We don't drink the fresh water, but we do use it to wash things and flush, so it's just one less thing to have to clean up when de-winterizing.
In answer to your question, I don't see why you couldn't drain your tanks, open the faucets and shower taps, and let your plumbing dry out some more, while you wait for your departure date in January. I would leave RVAF in the gray and black tanks to lube the valves. Just remember to close everything you opened, prior to recharging the system with water before or on your trip.
Good luck with it.
We love the southwest, too. :thumbup: