Meh, I pull the slides in when not in use.
No need to have any more of the trailer exposed to the elements than necessary.
Depending on your enclosure, this may not be an issue.
But, given how cold it can get in Gravelbourg, I'd say once they're out they're out for the duration. Once they're in they're in.
I wouldn't be running them in and out when it drops to -30/-35 C. Great way to break something or maybe tear a seal....
2011 Flagstaff Classic Superlight 831RLBSS "Atrium slide"
Husky Centerline Hitch
1998 GMC Sierra SLE K2500 6.5 Turbo Diesel