Should I retest my FTP in the middle of my training block due to a bike fit?

Hey everyone, I’m in the midst of a sweetspot base block on the high volume plan and I recently got a bit fit for the first time. Today was my first actual session since the fit, Juneau -1, and I feel significantly stronger in my new position (we made some big changes to all aspects of my fit). The session felt incredibly easy compared to other sweetspot workouts, and everything feels more fluid riding now which is great. Given the seemingly large positive impact this fit has had on my riding, would it be a good idea to retest my FTP in the middle of this block, or should I hold out 3 more weeks until my next scheduled ramp test?

I would. I just retested on a new fit. It’s a significant change. If you come in lower, it comes up as you adapt to the fit. If you come in higher, sweet!

I am experiencing a similar thing but in the opposite direction. Ever since I got a bike fit my heart rate has been significantly up (10-15 bpm) then what I am used to.

My previous fit was very poor. Enough where my saddle had to be raised by almost 4 cm. So the running theory is that in my previous fit I was mostly engaging my quads and hardly my calves. Therefore I am now engaging more muscles and increasing my oxygen demand. It is also worth noting that I took a week off the bike after I finished a build phase to rest and do the bike fit and accepted a new FTP (5 watts higher) and the higher HRs is during the first week of a specialty block.

Should I reassess my FTP or keep the new, higher one and presume my body will adapt? I am getting through the workouts, albeit with my heart rate 10-15 bpm higher, and I have been marking them hard or very hard.