Overview
- AT&T sent text messages Friday instructing U.S. iPhone 18 Pro Max customers to update to iOS 27.0.1 because some phones may be unable to complete calls, texts or data, including calls to 911.
- Users on Apple Support Community, Reddit and MacRumors report at least thousands of affected devices and say many still show SOS or lose service after installing iOS 27.0.1.
- Apple has not publicly confirmed that 27.0.1 fixes the AT&T connectivity problem and some users report that Apple tested devices and in at least one case offered a replacement despite finding no fault.
- Reporting highlights that U.S. iPhone 18 Pro Max units use a Qualcomm cellular modem while other markets use Apple’s C2 modem, a hardware difference that investigators are now scrutinizing but have not linked conclusively to the failures.
- If the root cause is software, Apple may issue another update such as iOS 27.0.2, and if it is hardware carriers and Apple could face broader replacements and regulatory scrutiny because of the risk to emergency calling.