..." I don't buy the roof needs to be fixed. The guys who fix the roof and drill the rock are different skill sets I hope."...
Schaft Creek Camp is a fairly small camp. I believe it is considered to be pretty full with about 40 people. Every good roof is important. The roof on the kitchen, for example would be critical; camp would not be operable. Somewhat similar for a geologist hut or the generator shack or bunk house, etc, etc.
If they had enough snow to damage roofs then there is probably a bit of it around in drifts or at the tails of the avalanche chutes like where DDH 422 is located.
I'm taking the drilling delay for the simple operational reason given.