"A" race in March, "A+" Race in August, debating risk/reward of a 10 month "double season" plan

My biggest race for 2020 is Leadville next August, but I am also planning to do the Austin Rattler race late March (60 mile MTB race). I’ll also do a bit of road and gravel racing throughout the year, but nothing to train around or taper for.

The timing actually works pretty well if I start a full training cycle first of October (next week), 3 months of SS base, 2 months sustained power build, 1 month specialty, taper and race in late March.

I was thinking I’d take an easy week or 2 after the Ratter and then jump back into SSB, sustained build, and specialty again. Rest/Taper first couple weeks of August and then race Leadville.

I am not planning to follow the TR plans exactly, but use a hybrid approach where I take the High volume TR workouts on Tues/Wed/Thurs, but continue my long Saturday rides outdoors. Sunday can be rest or something outside, but typically not a hard ride. With the big ride on Saturday and TR on Tue,Wed, Thurs, I should be in line with high volume TSS targets each week.

The whole plan lines up really well on paper, but I’m questioning the idea of 10 months of structured training without any significant break. My training approach in the past has been just riding a bunch of volume with a heavy emphasis on tempo work as my base and then a couple months of threshold and V02 work before big events. I always enjoy the tempo work, but I’m usually getting a bit mentally cooked after a couple months of Vo2 and Threshold work. So, I’m concerned about the mental side of structured training for that long and I’m also a bit intimidated by the SSB work compared to the tempo stuff I’ve done in the past for base.

My level of motivation is pretty high going into 2020 and I really want to get to “next level” for a good result at Leadville. That said, I’ve never tried to build fitness for 10+ months and I’m concerned it might not be a smart approach. Any thoughts/guidance from anyone who has tried a similar approach over an extended period?

I just completed the following all mid volume:
TB 1, 2, & 3, General Build, SSB 1 & 2, General Build, XCM Specialty

That was building fitness for 48 weeks taking me from October 2018 to my A race I just finished this past weekend on September 20, 2019. During that time my XC race season started in May 2019. I raced 7 XC races starting in May with my last XC race in late August 2019.

Building for that long went really well except that I got burned out towards the end of my second General Build (July 2019). I had a week long MTB trip to Scotland planned for the first week of August and I didn’t even feel like going. Worse yet, my supposed A race I started loosing interest in. In my last week of Build I took extra recovery to regain my mental ability and build extra freshness for 6 days of unstructured riding in Scotland.

That extra recovery and vacation MTB was just what I needed. I came back from Scotland and felt refreshed, ready to take on my last two XC races and specialize for my A race. So yes, you can “build” your fitness for 10 months, just listen to your body and rest whenever needed. If you even get the slightest sign of mental fatigue then back off training. Also, I’d plan a mid season training break of a week or two to refresh yourself.

Good luck!