Feel fresh day after VO2 workout

Just noticed that I seem to feel strong the day after v02 workouts. Finished my recovery week on Sunday with 400 tss( which was maybe too much). The 3 weeks before were 500tss, 600tss and 700tss. Felt pretty sluggish at the start of the week with Monday being a 2 hour Z2, Tuesday a 4 hour endurance, Wed a 1 hour easy, Thursday 7 x 3 mins at around 115 to 120% v02 max which went fairly well. Today I was going to take off but weather was good so headed out and done an 80min at 225 avg watts with an FTP of 250.( non structured over/unders really) but felt really strong. This is not the first time that I have felt kinda fatigued right after the recovery week but probably had my best workout a few days after the day after my v02 workout. I had been contemplating on Tuesday and Wed of taking another easy week but going on today I assume that that was not the reason I felt fatigued at the start of the weak. This week is up to 650tss so I will take it handy the next 2 days. Anyone else experience this?