I can't say for sure, but if that is the only other thing that has been different, then it seems sensible to wait until the stress is over before changing the hrt that worked for such a long time, just because it's so difficult to find a match to start with!
I've not managed to get rid of night sweats yet, they are perhaps fewer than 18 months ago when I first approached my GP for HRT, I still only get a 50 dose patch but I've noticed things improve if I "forget" to remove my old patch and have two on. Just a few hours for a boost rather than an increase that I'd let my body adjust to, left on too long I'll get ups and downs going from 2 then 1 which is worse.
Herbals that might help are valerian root for stress, melatonin for sleep, kratom for relaxation or black cohosh for heat regulation, if you are ok taking them of course. I've used all the above during peri alongside HRT, but not everyone's GP agrees on the safety of that and kratom can cause nausea on withdrawal if you overuse it. I'm not a qualified person btw, just interested in herbals.