Personally I’d do:
Ssb1 6 weeks
Ssb2 6 weeks
Build general (last 4 weeks)
Ssb2 6 weeks
Build short power 8 weeks
Specialty 8 weeks
I think this would be better than repeating base twice plus leave you with 2 ‘spare weeks’ for life/illness etc that are bound to occur over a 40 week period. I would always plan a little flexibility into my year like this. If not then do last 6 weeks of general build.
I recommended general build as will give a more around base before start to hone shorter stuff.
Would depend on current level of fitness. If already fairly fit and been doing fair amount of riding then maybe do ssb2 and part general build first, then full base, build, speciality.
If less fitness coming in I’d want to do full base first
I’d be careful stacking Builds. Ideally, IMHO, (and what’s been said on the podcasts dealing with extra time) you’d go:
Base / Build / Base / Build / Specialty
So Traditional Base 4 weeks, Build a weekness area, then SSB1 and SSB2, Build (specific to the event type) and lastly specialize leading to your A event.
Significant extra training time is usually best spent in Base. For me leading to my A event in September 2019 (Marji Gesick 100) I’m doing:
Traditional Base / Sustained Power (my weakness) / SSB1, SSB2 / General Build / Cross Country Marathon