Does an in-race FTP "test" count for Zones?

Did a gravel race this weekend and notched a new Training Peaks personal best for 20 minutes sustained power on a big climb. But there were super pitchy sections where I was pushing mid 300s and some slightly flatter areas where I was in mid 200s.

Since TP gave me a new All-Time 20 Max Power of 291 do I adjust my Zones accordingly? Or is this an inaccurate cheat?

Congrats!

FTP from races and group rides