Hi Les,
Your timing for questions is good. Just a few minutes ago I spoke with CBSA in Sidney BC, to verify my understanding of the "Transit through Canadian waters" rules. No surprises, except that I do need to fill out the info requested by the ArriveCAN app. And submit my written travel plan too, showing likely anchorages and fuel stops.
I'll check in at Sidney. Can't anchor before checking in, so Sidney works for me traveling at 7 knots.
A negative COVID test is not reqd.
Stopping for fuel/water at a place declared as a possibility in my written plan is fine, no additional call-in reqd (unless I have to make an unplanned stop).
No shore trips other than the fuel stops. No wandering around sightseeing. No tying up to other boats. No fishing.