well for me, i've noticed it move that direction, not necessarily land at 5.4. if I target 5.25, and first PH reading is say 5.18, i leave it alone and it moves up at or near my intended target some point during the mash. same thing like what happened today-only the inverse. i started out 5.54 with target of 5.45, and the PH landed at 5.42 when measured at end of mash.