Re: Mixing hay
I also, living near Banff, have soaking hay in winter issues. I did do it for a while into freeze by hanging one flake per net in a shed with a space heater drying it a bit. I also used an empty stall space in my run in shed with matting on the floor to shake and mix hay varieties. As the others have mentioned this brought the overall percentages down.
I also laid some soaked hay out over snow fencing and saw horses to dry a bit longer and in our dry air it did, not sure if that wouldwork for you but your cold shouldn't be as deep as our minus 30 either.
I was, possibly over careful on mixing, but I did want to make sure that the high sugar starch hay was well mixed in hoping this would help keep spikes down and encourage the eating of all the hay, not just going after the "candy" first.
Rocky Mountains, Alberta, Oct 2020