Does the modeled FTP power ever go down?

Not sure how the algorithm determines FTP but I’m pretty sure I can’t sustain 314W for an hour.
I notices the number inches-up with longer harder rides, but there’s no correlation with my actual power curve (As in GoldenChetah or WKO+).
As a result I can’t get to a new breakthrough, even if my CTL is growing. What’s missing?

Threshold Power:
316W
6 Minute Power:
367 W
Training Status & Form:
Last Breakthrough: SBC: Over/Under 2x9 - 1 month ago

If you feel that there are errors in your progression, flag the corresponding activities with breakthroughs. This should bring back your progression. If you’ve had a long period of Training Load increase, you very well may have a latent breakthrough coming and may indeed be surprised at what you may be capable of. If you check the FB Users Group, there are many stories of athletes saying the didn’t believe what Xert was predicting until they tried it. With Xert giving them the added belief they could do it, gave them the motivation to achieve it.