Apple Stops Signing iOS 15.3.1 Following iOS 15.4 Release, Downgrading No Longer Possible

Following the release of iOS 15.4 on March 14, Apple has stopped signing iOS 15.3.1, the previously available version of iOS that came out in February. As iOS 15.3.1 is no longer being signed, it is not possible to downgrade to that version of iOS if you've updated to iOS 15.4.

iOS 15
Apple routinely stops signing older versions of software updates after new releases come out in order to encourage customers to keep their operating systems up to date, so it is not unusual that iOS 15.3.1 is no longer being signed.

iOS 15.3.1 was a bug fix update that addressed WebKit vulnerabilities, while iOS 15.4 was a major update that added new emoji characters, Face ID with a mask support, and tons of other features. Apple has also stopped signing tvOS 15.3.

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Top Rated Comments

Black Magic Avatar
40 months ago

I'm still on iOS 14, but it looks like I need to upgrade since a policy at work requires I am on iOS 15 in order to use the internal Wi-Fi. I am going to try to hold out for iOS 15.5.1 though.
You holding out for what? You denying yourself great features thinking you are saving yourself from bugs and headaches? You like 2 years behind the curve and you feel like that is something to brag about?
Score: 9 Votes (Like | Disagree)
Y014951 Avatar
40 months ago

What features am I missing out on exactly that are so detrimental? I have been doing this every year since iOS 11. At the end of the day, it’s about the apps. iOS is just an OS. Most of what I already need in terms of integration doesn’t require iOS 15.
I honestly don't understand the downvotes. Mr. Dee seems to be a quite active participant in the Macrumors forums so I believe he knows what features he's missing. It's his decision to update his devices (or not) after all...
Score: 7 Votes (Like | Disagree)
Black Magic Avatar
40 months ago

What features am I missing out on exactly that are so detrimental? I have been doing this every year since iOS 11. At the end of the day, it’s about the apps. iOS is just an OS. Most of what I already need in terms of integration doesn’t require iOS 15.
Your employer is trying to nudge you into the present. You are obviously missing the point.
Score: 5 Votes (Like | Disagree)
now i see it Avatar
40 months ago
and good riddance
Score: 4 Votes (Like | Disagree)
canadianreader Avatar
40 months ago
We need the right to downgrade. I hope sideloading will open that door.
Score: 4 Votes (Like | Disagree)
Mr. Dee Avatar
40 months ago

Your employer is trying to nudge you into the present. You are obviously missing the point.
The same employer who has Windows 7 clients all over its network?
Score: 3 Votes (Like | Disagree)