Catherine, hon, I think you're starting to get into the "not the subject of any study" area, which is why there's a dearth of answers.
One of the reasons they don't use the rises from baseline for hypertension dx is because BP isn't something they document well in the first trimester most of the time. Heck, where I normally get care- the first prenatal visit isn't until 12 weeks, second trimester!
Regardless, rises from baseline are always something to be watched with a great index of suspicion- hang in there- it's not necessarily diagnostic. As the hallowed Dr E once said- it means- I don't know, so I will wait and watch.
Besides, if you end up with a dx of chronic htn will you be terribly surprised? Hey- at least they tend to treat chronic htn a whole lot more than it's gestational cousins- IMO, a good thing!
Side note- I think my home BP cuff is complete junk- I've been taking my BP at home- thought it was fine- turns out- I've been in the 160's-170's/95's Whoops! Moral of the story? Unless you know you're calibrated beautifully- avoid the home monitors!
Allicia 5-13-98 (35 weeks-pre-e)
Camille 4-17-03 (36 weeks- htn and oligo)