Apple has launched a revised AirTag firmware carrying an internal build number of 1A291c while the firmware version has remained unchanged at 1.0.276.
Apple drops revised AirTag firmware with internal build number of 1A291c

Apple has launched a revised AirTag firmware carrying an internal build number of 1A291c while the firmware version has remained unchanged at 1.0.276.
In a somewhat predictable fashion, Apple closed the short-lived signing window for iOS & iPadOS 14.7 on Monday, almost one full week after unleashing iOS & iPadOS 14.7.1 upon the general public with important bug fixes and security patches for its mobile devices.
Following a lengthy beta testing period involving developers and volunteer participants, Apple officially released iOS & iPadOS 14.7 to the public last week with a long list of new features and improvements for iPhones and iPads alike. But no software update from Apple comes without the bitter aftertaste.
Just as Apple always does after releasing a major software update, the company closed the signing window for iOS & iPadOS 14.6, which makes it substantially more difficult for iPhone and iPad users to downgrade to the older firmware version if they’ve already updated the device(s) to iOS or iPadOS 14.7, or perhaps the newer yet iOS or iPadOS 14.7.1.
Apple is now testing upcoming AirPods Pro firmware that will bring software support for some of iOS 15's audio features like ambient noise reduction and spatial audio for FaceTime calls.
Apple released iOS & iPadOS 14.6 to the public in May with some improvements for the company’s mobile operating systems, and as we know with most of Apple’s mobile software updates, they typically come closely trailed by the un-signing of the previous version.
That’s the case this evening, as it appears that Apple has officially stopped signing iOS & iPadOS 14.5.1. With this move, iPhone and iPad owners will no longer be able to easily downgrade from the newer iOS & iPadOS 14.6 using traditional methods.
In a typical Apple fashion, the Cupertino-based iPhone and iPad manufacturer has stopped signing both iOS & iPadOS 14.5 after the newer iOS & iPadOS 14.5.1 firmware has been available to the general public for one week.
Apple’s decision to stop signing iOS & iPadOS 14.5 means that those who’ve upgraded to iOS or iPadOS 14.5.1 can no longer easily downgrade to the previous firmware. Likewise, those using even older versions of iOS or iPadOS will be compelled to upgrade to version 14.5.1 instead of being able to manually install 14.5 via Finder or iTunes.
After officially launching the highly anticipated iOS & iPadOS 14.5 update a week ago with support for Face ID authentication while wearing a mask and 5G connectivity whilst utilizing dual SIM mode among other things, it should come as no surprise to anyone that nearly one week later the Cupertino-based company is pulling the plug on the previous iOS & iPadOS version — 14.4.2.
Apple’s decision to stop signing iOS & iPadOS 14.4.2 means that iPhone and iPad users will be unable to downgrade to this particular version of Apple’s mobile operating systems under most circumstances, with the lone exception being that users have their .shsh2 blobs saved from a time when that firmware was being signed.
Apple released iOS & iPadOS 14.4.1 last Monday alongside similar updates for macOS and watchOS with security vulnerability patches. But as many already know with Apple’s rather frequent software updates, it’s never long after a release before the company stops signing the previous version of its mobile operating system(s).
Such is the case with iOS & iPadOS 14.4, which Apple stopped officially signing just this evening. This move on the Cupertino-based tech giant’s part means that iPhone, iPad, and even iPod touch users will no longer be able to downgrade their firmware from iOS or iPadOS 14.4.1 to the older iOS or iPadOS 14.4 release.
The latest AirPods Max firmware that arrived earlier in the week appears to have fixed the issue affecting some units that were plagued with excessive battery drain while in the Smart Case.
Excellent news for those who’ve been wanting to take advantage of futurerestore to downgrade or upgrade to an unsigned version of iOS or iPadOS – you’re no longer limited to using command line interfaces (CLI) to do so.
On Monday, the community was pleasantly surprised by the release of a new user-friendly and Java-based futurerestore application for macOS dubbed FutureRestore GUI (GUI of course stands for graphical user interface).
Apple regularly releases software updates for the company’s many platforms, mobile and desktop alike. Interestingly, while most Apple’s software updates target either newer devices or upgrading the user experience of the company’s latest firmware iteration, a few heads turned when Apple released iOS 12.5.1 earlier this month to address a COVID-19 exposure notification bug that purportedly affected older iPhones.
Given that a software update was released, despite being for an older iteration of iOS, it should come as no surprise to anyone that Apple would soon close the signing window for what was previously the latest version of iOS 12. This happened Tuesday evening after Apple officially made the move to stop signing iOS 12.5, the predecessor of the newer iOS 12.5.1 update.
After officially launching iOS 14.3 to the public last month with new features and improvements, Apple has closed the signing window for iOS & iPadOS 14.2 & 14.2.1, a move that prevents affected iPhone and iPad owners from restoring their handset’s firmware version to anything but the current iOS & iPadOS 14.3 release.
In addition to iOS & iPadOS 14.2 & 14.2.1, the company has officially started unsigning iOS 12.4.9, which prevents older handsets that are incapable of being upgraded to iOS or iPadOS 13 from downgrading from the newer iOS 12.5 release.