Overview
- On August 5, Apple officially ceased signing iOS 18.5, preventing any device running iOS 18.6 from reverting to the previous version.
- The signing process relies on a server-side verification check that rejects outdated firmware once the grace period ends.
- iOS 18.6 was released on July 29 with more than 20 security patches and critical bug fixes.
- Apple generally shuts down signing windows a week after a new release to encourage rapid adoption of security updates and thwart jailbreak methods.
- Owners of older iOS versions can still install iOS 18.5 within 90 days of unsigning by using the DelayOTA upgrade workaround.