With a low volume plan you might not need a two week taper. It’s good to experiment with different lengths of taper to see how you respond, I always feel a little flat after a full two weeks unless I am carrying a lot of fatigue into it.
I am also going with the General Build this year for XCM races, it seems to strike a good balance. I would recommend extending out your Sunday mtb ride into some fairly long rides leading into the race. The course has changed a bit over the last couple of years but if you look at last year’s profile it looks a little like it is all generally downhill after that big climb ending 25 kms into the race. It definitely does not feel like that, there is a lot of punchy climbing and physical descending from that high point and it’s good to have your body used to longer mtb efforts leading into the race.
If the Sp’akw’us is one of your A races racing one of the other local XCM races in May (Vedder, the Sunshine Coaster or the Nimby (maybe sold out)) would be good preparation.
Good luck!