How to maximize one month of increased training/recovery time?

Hi All, I have an opportunity to increase both my training and recovery time quite significantly for a one month period and I’m looking for advice on the best approach. I’m currently planning a 3-week overreaching period, followed by a week of rest, where I’ll be significantly increasing volume. I’m torn between a long slow distance approach or following 3 weeks from the SSB HV plan. My goal is to increase aerobic endurance and FTP. A few important variables:

  • I have 3-4 years of structured training history and feel I’ll be able to handle the increase and know when it’s time to dial things back - - TrainerRoad
  • I will be coming off a Vo2 block and rest week, FTP was stagnate and thought it was time to raise the ceiling.
  • My A race this year is a 3 day 300 mile ultra bike packing race at the end of July
  • My training will be time-crunched following this month period, with a long z2 ride sprinkled in every other week
    *I have responded well to increased volume in the past, did a short volume “camp” last Spring and saw nice fitness gains

I thought it might be a fun question for the collective training knowledge of this group and something that may benefit others in their training. Let me know if there are any other details that would be helpful. Appreciate you giving this some thought!