Unfortunately, the usual warning that you see on drugs are accurate, "Results may vary." There's a lot of variable factors that affect how much the hormones/anti-androgens can do. For some people, they see their hair completely disappear, while others hardly notice any change, and then there's everyone else in between. You should never get your hopes up that HRT will affect everything to the full extent.
Also, 13 months isn't an extremely long time to be on HRT yet, so more results may come later. As far as whether you should stay with the current dose or go back, I'd say just make sure you're within a safe dosage to get the desired results. If you're not seeing results by the increase then definitely go back down as it's unsafe and not beneficial to go beyond HRT's maximum effective dosages.