Help explaining new hair regrowth

[RickySpanish]

So some background. I noticed my hair started thinning and slightly receding at 17, so I started on regaine, using it on the back and hairline of my head, that slowed the loss down to a crawl and i noticed a little bit of regrowth in my temples.

fast forward 8 years and I started to look noticeably balding, so I started on Finastride 1mg a day, I recovered a lot of lost hair at the back of my head within a few months but nothing really on my front hairline but i carried on using it.

I've been on this treatment for 2 years now and denser hair and more coverage on the top/back of my head and I seem to have stopped losing hair at my hairline and along that horse shoe shape across the front of my head.

However, as of the last month or so, pretty much exactly 2 years after I started thse combined treatments I've observed that along that horseshoe shape my hair is now basically the same density as the rest of my hair, I no longer have noticable indents into my hairline above my temples and I have new hair growing below where my hairline starts.

This sounds great I know, but the trouble is I haven't changed my routine and I've never read that you start getting results 2 years after starting finasteride. Basically because I don't know what caused these results I'm terrified of losing them so I'm hoping someone on here might have an idea, my improved hairline started roughly 2 months ago I have had;

No changes to my hair loss treatments, no change in what styling products I use or washing routine.

I have had some lifestyle changes but I can't imagine how they've affected my hair namely: i've stopped working out because of a heavy work schedule, I've also put on about 30lbs since lockdown, I've stopped taking prozac but hair loss isn't a side effect apparently, I still drink and smoke just as much as I always have, I've started sunbathing more because it's summer and that's basically it.

Anyone have any ideas based on the information? I really don't want to lose this new growth