Apple has changed its policy for iOS 14 update support policy, different from what they promised before.
When Apple launched iOS 15 last fall, it promised that users who didn’t want to upgrade from iOS 14 would still receive important security updates. That option seems to have disappeared recently when the company confirmed this week that it always intended to bring all iOS 14 users to iOS 15.
This comes after the last security update for iOS 14, iOS 14.8.1 (along with iPadOS 14.8.1), was released in October. And notes from 9to5Mac indicate that iOS 14 users are currently using iOS 14. now can’t update to that version anymore, instead the only one that appears now is iOS 15.2.1. Apple later confirmed to Ars Technica that this was set by the company and that the ongoing security updates for iOS 14 should only be considered a temporary grace period.
Apple never mentioned this when it first announced and rolled out iOS 15. In fact, the list of features for iOS 15 so far indicates that iOS 14 users can still get it. security updates without mention of deadlines. Because iOS 15 is compatible with all iOS 14 devices, there are no hardware conflicts, so users can be more secure in updating.
It is likely that Apple will be a bit more explicit about its security update policy for the iOS operating system in the future.
Source: http://danviet.vn/apple-lat-long-ep-nguoi-dung-iphone-xai-ios-15-50202211119307409.htm

Accordingly, Apple will stop providing security updates if users do not upgrade their iPhone to iOS 15 version.
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