If making in a casserole, line the casserole with freezer foil. Oil it. Put in the stuff, and don't mamke it much over an inch thick. Freeze it as quickly as possiblw (large freezer, few pies). Close the foil over the item, pop out of the casserole and bag it up. To cook, you pt it back in the caasserole, but in the meantime, you have your casserole free.
I would put the puff pastry on when I reassembled it to heat. Unlike regular pie crust, puff pastry doesn't like likes of handling. I rarely work with this myself...
When you get a really successful recipew, send it in and I will put your name on iy and post it on the OAMC freezer cooking pages.