Are you located in the northern hemisphere?
I know for me when winter is on it's way in my body hair seems to kick into a higher gear. It's still nowhere near pre-HRT amounts but it does increase.
I had said something about it last time I got my eyebrows waxed to the lady who does mine and she said that happens to everyone this time of year.
Just a guess but it could be nothing more than a change of the seasons....