The moose mostly are in pre-rut, but will come to calling. Active rut starts last few days of September, runs into Nov sometimes with second estrus cows Meat should be good, but exceptions can occur, especially if you kill one that has been fighting, is gored up and infected. I prefer Sept 20 as cut-off date, but the 24th is pretty safe. Past the 25th is chancy, at best- I shot one on the 29th that was right rank, and he hadn't been fighting. I would not shoot a bull before November 10 now, either. That one I killed on Nov 1( first day of after-rut bull season) was out of rut, but still had a smidge of rut not out of him. I won't shoot a November bull before the 10th now. If ever. Cows are in (hunting) season then....
You need 10 heavy duty game bags. More if you want to change some out due to wet, blood, or tears.
Your 0 degree bag may require wearing several layers of clothes to bed. I was out last weekend with a 0 degree bag and maybe 28 degree night under a tarp (frost on vegetation, very light skim ice on small, shallow puddles between tussocks) , with a light wind. (inside a tent will add a few degrees- especially if a heated wall tent) Always figure 10 to 15 degrees "rated to" below your expected low night temperature - and even then you might need some clothes in bed. Their ratings will keep you alive, but probably not sleeping comfortably. You can always open it some if too warm.
Often, I prefer taking extra clothes and only a "marginal" bag, for the above reason - I can change out of wet ones, and wear dry ones to bed. And dry one set while wearing the other. Another trick is to wear head covering, ski mask and or neck covering to bed. 75% of your lost body heat is lost through the head and neck area. I like dry socks in bed too- it feels so decadent...
Should have brought my -15 bag last weekend, but a light jacket over my regular clothes inside the bag, and my breathable rain coat over the bag took care of that. Exposure to that light 5mph wind didn't help! .
Caribou should be good thru your time frame. They have about the same rut schedule as moose. You definitely do not want a magnificent, white-maned, "stink-bull"s in their rut. Gag a maggot!
