Apple shipped iOS 27.2 on October 26, and the usual rule says the older version should already be gone. It is not. As of a signing check run on the morning of October 28, iOS 27.0.1 is still signed, which means a compatible iPhone can still be restored or downgraded to the version Calif used for its untethered jailbreak demo in Paris. The window is open, but it can close without warning, and that is the whole story today.
This matters only to a narrow group, and we will be blunt about that. For almost everyone, iOS 27.2 is the right update, and our report on its release explains why: 163 CVE fixes, Calif credits in the notes, and researcher Stefan Esser’s statement that most of the Hexacon chain is patched. The signing news changes nothing for readers who already updated and are happy there. It changes everything for readers who updated by accident, or who were still deciding, because a downgrade is only possible while Apple keeps signing the old build.
What the October 28 signing check actually shows
ONE Jailbreak’s signing status page, updated on October 28, 2026 and crawled at 09:08 UTC (14:38 IST), lists iOS 27.0.1 among the versions Apple is still signing, alongside iOS 27.2, iOS 27.1, and iOS 26.7.2. The page draws its release firmware data from ipsw.me and says it tracks Apple’s signing servers minute by minute. Its own FAQ puts the usual window at 7 to 14 days after a new release, which fits what we are seeing: two days after iOS 27.2, the old version is still alive.
Two cautions belong in the same paragraph. First, signing is per device, not global. A version listed as signed in general must still be signed for your exact model, so check your model before you start anything. Second, a signing page is a snapshot, not a promise. Apple has closed windows in the middle of a day before, with no announcement, and this page will simply flip from signed to unsigned when that happens. Treat today’s status as today’s status, not as a deadline you can plan around.
The iPhone Duo is in the same position, on iOS 27.1
The same October 28 check lists iOS 27.1 as signed. That is the version that ships on the iPhone Duo, and it is the version our Duo guidance told owners to hold. Duo owners who moved to iOS 27.2 still have, as of this morning, a signed path back to 27.1, just as other iPhone owners have a signed path back to 27.0.1. The two groups are in parallel positions, on different builds, for the same reason: Calif jailbroke the Duo on its launch-day firmware, and the Paris demo ran on 27.0.1.
Redmond Pie reached the same conclusion late on October 27, advising readers who want any shot at a jailbreak to stay on iOS 27.0.1, or downgrade to it while Apple is still signing the old firmware, in case Calif changes its mind about releasing its exploit. That advice only works while the window holds, which is why a dated signing check is news rather than background.
What a downgrade actually costs you
A downgrade is not a settings toggle. It means downloading the IPSW firmware file for your exact model, connecting the phone to a computer, restoring through Finder or iTunes, and setting the phone up again from a backup. Restoring firmware wipes the phone, so a current backup is not optional, it is the whole plan. Our update-day checklist covers the backup steps, and they apply in reverse here too: back up first, confirm the backup, then touch firmware.
There is also a backup trap worth naming. A backup made on iOS 27.2 cannot be restored onto iOS 27.0.1, because Apple does not allow restoring a newer backup onto an older version. If your only backup is from after you updated, a downgrade means starting fresh or using an older backup. Anyone considering this should check the date of their last pre-27.2 backup before downloading anything.
What this does not promise
Nothing about the signing window changes the state of the jailbreak itself. Calif has said it has no plans for an end-user tool, although a proof of concept may come at some point. Esser has said most of the Paris chain is fixed in iOS 27.2. No tool exists today for iOS 27.0.1, iOS 27.1, or iOS 27.2, and any site offering one is selling something that does not exist.
So the honest framing is narrow. The open window preserves a possibility, it does not create a jailbreak. Downgrading to 27.0.1 keeps you on the version the demo ran on, with its known security gaps, in exchange for a chance that may never pay off. That trade made sense for researchers and for the small number of people actively following this story, and it never made sense as general advice. If you are not in that group, stay on iOS 27.2, keep Automatic Updates on, and let this window close behind you without a second thought.
We will keep checking the signing status, and we will report the day it flips. Until then, the decision that could not wait yesterday still does not have to be rushed today, but it cannot be postponed indefinitely either. That is what a closing window means.
