My FTP has dropped

Not Worried though, as there are some very positive aspects. Ive lost only 8 Watts, my cadence was more than 10 Revs higher, The FTP routine includes a 5 minute pre FTP test where you go pretty much all out, and I didnt fade towards then end of the 20 min test.

Lots of positives to take into the 'Power Build' phases. Again this block looks quite intense with some 2 hour tempo interval sessions

. But. but trainer road says that Iron-man triathletes ride at this zone for 3-4hours