Flatline - does it appear every time you abstinent even when you are already rebooted?

Hi guys, I have that question.

Basically I thought I was rebooted, PIED was gone, I stopped liking my old fetish a now I prefer just pure normal sex.

My first challenge I hit flatline on day 16 to day 44. I considered it to be normal as part of healing process. After getting out of flatline things got much better.

Now I decided do to another challenge just to abstinent from masturbation in general as I see huge benefit in it. I feel really rebooted,no serious problems and therefore I was so surprised to hit another flatline and even on exactly same day (day 16) of my second challenge.

Does it mean I am not 100% rebooted?
Or it means that flatline appears everytime you abstinent from orgasm for longer time even if you are perfectly fine and rebooted?