Will both OS versions Android 7.1.1 and 8.0 Oreo Beta continue to receive monthly security patches?
May be yes, may be not. It's more a question of luck. I got my last security update on the Nokia 3 (TA-1032) in November 2017. Since then, no updates. Nokia is not really interested in updating their low range consumer phones regularly. At least they don't tell, why they are not updating it.
I even did a complete hard reset of the Nokia 3, so that all the system components were enabled again. It didn't help. There seem to be (unlocked) TA-1032 models out there, which in combination with SIM cards from some international network providers do not receive security updates. Even removing the SIM cards and resetting some framework did not help to receive the updates. Tells me, that it does not seem to be so easy to provide updates on a regular base, but then Nokia should not promise it to everybody...
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