Looking at the webcams it looks like Fernie is still "bare" for Fernie standards. Some good snow but looks like a lot of the off-piste still doesn't have enough snow to cover it, and the off-piste is what Fernie is really all about.
Kicking Horse is also owned by RCR so they could probably transfer your reservations without penalties, and the drive from Calgary is the same to KH as it is to Fernie (+- 15 mins). The snow's looking better at KH and if it turns out shitty you could always go to Lake Louise or Sunshine which seem to be getting dumped on.
I've only been to Nakiska so far this year, and last I checked there wasn't that much open yet. That was last week though...
Seems like Sunshine has the most open so far. KH is targetting Dec 7th I think, I'm going to try to be there for opening day.