I think the premise is that the body responds better to long training cycles that have peaks and “down time” so like annually we have off season then base, if your race is next summer, personally I would take time off now, ride regular but unstructured until it gets too cold then have plan builder line you up. But yes, you can do base/build cycles if you prefer.
As you have long course experience, if you’re anything like me you’ll enjoy the short/sharp olympic training as I did this year.
Check out the short course tri thread as you may get more responses there:
I haven’t done XC tris but I’ve seen people use the TR tri plans for them - it’s different to road but it’s still all about aerobic endurance 
