well if we postulate the half-life of LR3 to be 48 hours (just for argument's sake), a 100mcg level, and a 100mcg final dose (and assuming unsupplemented IGF levels to be zero), all LR3 should be out of the system after a week. IIRC, endogenous IGF lasts only minutes, I believe - maybe hours, but not days, so IGF receptors should therefore be quick-clearing. LR3 may have a longer life, but it doesn't stick around, either (apparently).
I'll bet a staggered dosing such as 5 on / 3 off would take care of any "receptor clogging", if that's actually an issue. Not that I'm recommending it: IMO maintaining constant levels makes more sense.