Best to not do OTA system updates/upgrades on Android phones.

Forced OTA auto-upgrades in iPhones and Win 10 computers have given a lot of problems to users, even bricking the expensive devices. If possible, do non-OTA or local OS updates/upgrades via a downloaded Stock ROM or firmware on a microSD card or a Win 10 ISO file on a USB flashdrive.

In the old days, we never do OTA Windows upgrade, eg from Win XP to Win 7 or Win 8 = very few complaints about OS upgrade problems.

While having a running-smoothly Android system, OTA-upgrading to the newest OS means nothing if you cannot run it smoothly like before. Why take the risk.?

Like they say, "Do not fix what ain't broken."
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