I don't think you need to park it at all if it's going to be powdercoated. More corrosion resistant? My powdercoating job is weatherproof, The PC is thick and clear coated. True enough I've not had it out in the rain yet but I have every confidence that its waterproof, especially if one cleans the gun after the wet hunt (inside).
The rough part about the PC that I got into...First, they wanted me to disassemble the piece completely (not bad), and they didn't tape off the innards very well or on the end of the barrel, so when I got it back it took awhile cleaning and polishing the barrel end and inside the receiver so the dang thing would even go back together. It took a while and some patience to get er back to the super slick action she once was. The bead is easy, run a knife blade around the crack and the PC cracks right off the bead leaving it nice all the way up to the bead. Dremel & polishing paste for the inside of the receiver.
I got a 2nd barrel for mine (18" police trade in), and an extended magtube, and had them done too along with the original mag tube cap so on hunting day everything will be limit legal and matching finishes.