In my case yes. With an extender routine I started getting flaccid gains within a month. Did not get any PEPL gains until after 3 months.
I also notice that I get BPFSL (in the extender) gains before I get any in BEPL. Understand this is quite common.
Believe the early flaccid gains are related to ligament stretching which is part of conditioning.
>(if so then maybe cause the body is able to fill in the nerves and blood pressure to support inflating a bigger flaccid.)
Not sure that is right. May have more to do with the need to stretch (grow) the tunica before you get gains in BEPL