Madwil,
Actually, I did not add any more chlorine (bleach 6%) after the 4:30 p.m. reading – my guess is two fold, 1) the overall total chlorine added for Monday was ~ 19 gal., and 2nd ) with the periodic brushing of the sides & bottom (filter passage, sock in skimmer basket, etc.) – it took an extra amount of time for the FC to rise! Beyond that thought I’m kind of struck as to why as to why it increased overnight?
Your recommendation to continue for another day (or 2) is in line with my thinking – although today I have not been as punctual as I was yesterday – a holiday! I’ll be very happy to finally get ride of the BaquaGoo!

Gene