Training Plan Pre and Post COVID-19 Lockdown Where did I go wrong or improvements for 2021

Pre COVID-19 (32 Days ago) Training Plan:
Objective: 3 Day Ultra MTB Stage Race “Mediterrean Xtrem”(Day 1 150km, 4000 meters climbing; Day 2 60km 1800 meters climbing; Day 3 120km 2200meters climbing)

Training Plan: TR Plan Builder Low Volume (essentially 3x HIIT per week) + Starting in December I added on weekends two MTB rides between 2.5hrs - 6hrs

COVID-19 LOCKDOWN 32 DAYS ago Spain went into hard lockdown So instead of losing all my fitness decided to adjust Tng plan to all indoor(did’nt really have a choice :grin:) plan via TR Plan Builder:

Maintained the 3 day Low Volume + added 20min or some combination thereof to the warmup and kool down for each HIIT workout; Additionally, added 3 days of low aerobic endurance).
Note: 1

  1. HIIT workouts were only executed based on HRV balance during 6 weeks of training 2 were recovery weeks and 12 HIIT workouts scheduled 11 executed based on HRV balance.
  2. Tune up race was executed mid Feburary a 4 stage MTB race but much easier than the 3 stage A race.
  3. Base training started in August with a mix for TR and outdoor workouts both road and MTB.

Tell me were I went wrong or modifications for 2021.