Apple has now discontinued the verification of iOS 15.4.1 following the release of the official version of iOS 15.5 the previous week. Users who have updated to iOS 15.5 will no longer be able to downgrade to iOS 15.4.1 after the release of this software update.
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In addition to other features and bug fixes, iOS 15.5 brings improvements to Apple Podcasts. Additionally, the baseband has been upgraded to 1.61.00 in order to improve the signal performance of iPhones.
It was also discovered that Apple typically stops verifying earlier versions of iOS within a few weeks of releasing an official update to that version of the operating system. When using the most recent version of iOS, some users may find that the downgrade approach is their best option in the event that they have significant bugs after installing the update.
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Because of this, Apple waits for some time before finally shutting off the authentication channel for previous versions of iOS. The issue where the battery on an iOS 15.4 device drains too quickly has been fixed in the previously released version of iOS 15.4.1.