Vodafone has been warning its iPhone 4S customers in the UK to avoid Apple's iOS 6.1 update because of a bug that's causing 3G connection issues. Austria's Three has followed suit and is warning its iPhone 4S customers to avoid the update, too.
Vodafone warns UK users of iOS 6.1 3G issues
In a blog post for customers, Vodafone stated,
Some customers may occasionally experience difficulty in connecting to the network to make or receive calls or texts or to connect to the Internet. Apple is working on a solution to their software issue. These connection problems are intermittent.
While Apple's investigations continue, we would recommend that anyone who has not yet installed iOS 6.1 on their iPhone 4s should delay doing so until Apple has confirmed that their problem has been fixed.
Three followed up with a statement on its Facebook page that reads in part (thanks to the magic of Google Translate), "The update of the iPhone 4S on iOS 6.1 can currently cause connectivity problems. We responded quickly and are working with Apple on a solution to the problem."
3G connectivity doesn't seem to be a problem in other areas, although there does seem to be a relatively wide spread power usage problem in iOS 6.1. Comments on Apple's own forums talk about fast battery drain issues after upgrading to iOS 6.1 on all iPhone models including the 5.
Apple hasn't commented on the battery drain issue, but the statements from Vodafone and Three indicate that the company is at least working on the 3G connectivity problem.
]Thanks to The Guardian for the heads up]