Apple today officially closed the downgrade path to iOS 15.4.1 and iPadOS 15.4.1 after successfully releasing the iOS 15.5 and iPadOS 15.5 updates to the public a few days ago.
Thus, if the user has downloaded and installed iOS 15.5 and iPadOS 15.5, they will no longer be able to downgrade to any version of iOS or iPadOS anymore.
Apple also strongly recommends users to immediately download and install the latest updates because in addition to bringing new features, it also brings various bug fixes and system improvements.
iOS 15.5 and iPadOS 15.5 itself bring several new features. For example, Communication Safety, Wallet application updates, bug fixes in Home Automation, and so on.
How? Have you downloaded and installed the latest update?
Hi tweeps, please mention if you have any problems, questions, or just want to chat about iPhone, Mac, iPad, etc. We are ready to help ^^
— MacPoin (@MacPoin_ID) August 19, 2016