Last year android 11 update i install after 1 hr of releasing and i face more lags more battery drain that why my motherboard has been dead and go to coustmer care they suggest you install the any ui update not security patch update only ui you insta...

Because some bugs like lags are fixed in 24 hrs

I buy samsung a31 in 2020 and i install it after 24 hours release

Because i download this version after 24 hrs releasing in india

No i don't face any problems in samsung a31