You’re right that there is not any guidance for 12 month plans. It’s pretty hard to do more than a very general ‘big picture’ plan that far in advance. If your goals are all running related and going to take place next spring/summer/fall then I would keep building base all fall and winter using a 6 month plan that finishes with a B/c race. You’ll want some recovery after that race then roll into one of the existing plan templates for a mutli-race season.
You do not say the length of any of these races are. Normally the shorter the event, the more “intense” is the effort. Longer races must by necessity be done at a low intensity or you won’t make it. If these are long races (over 2 hours) then we’d normally plan to be building volume all the way to the A race. I’d not recommend much taper/sharpening for the C/D races. These should be planned to fit into your normal training scheme. You train through them, using them as workouts. The B race will want a mini taper.
I hope this helps.