Just last Monday, Apple released iOS & iPadOS 15.5 to the general public with changes for Apple Cash and the Podcasts app, and as many would come to expect, this move also meant that Apple would stop signing the older iOS & iPadOS 15.4.1 in the near future.
iPadOS 15.4.1
iOS 15.4.1 addresses iPhone battery drain (and iPad, too)
Apple has released iOS 15.4.1, a bug-fix update that resolves iPhone battery drain while addressing issues with some Braille and MFi hearing devices.