When I first started TTCing, I used to test from about CD30 onwards (using Fortel Ultra), and repeating it every couple of days (which is a LOT of HPT when you have 80 days cycles LOL).

With my most recent cycle, I couldn't bear the thought of seeing another BFN, so I didn't do any HPT at all. Getting AF seemed less disappointing that seeing yet another single line. I actually had thoughts of waiting until AF was a few weeks late, then going straight for a blood test, so that I wouldn't have to see another BFN.