Talking [Q] starnge problem with my Xperia acro s

hey guys, i have an acro S, its bootloader unlocked and rooted, with 6.2.b.0.211 firmware, a while ago i got an anoying notification saying that there is an update, so i tried to update but because its rooted it wouldnt update the normal way, then i flashed 6.2.b.1.96 kernel only, it was good for 2 weeks, but then today i got a red led, and screen was black, then i almost got a heart attack because i knew it was soft brick or something, i read about it and searched for fix, but after a moment when i tried letting the phone on wall charger till red light disapear, the screen went on, and every thing was normal, relef , so now i wanted the experts to know about that, and i want to ask for a stable way to get a rooted full 6.2.b.1.96 firmware, or the latest, or even a custom room if its better than the xperia one, tnx for reading and hope you all a brick free day XD