Last week, AT&T slightly loosened its restrictions that previously required iPhone users to who wanted to use FaceTime over cellular networks to be on a Mobile Share data plan — the carrier said that iOS users with an LTE device and a tiered data plan would be able to use the feature. However, we have confirmed that some iPhone users with grandfathered unlimited data plans are also able to make FaceTime calls over cellular networks, corroborating earlier reports. Strangely enough, AT&T said earlier that FaceTime over cellular for users not on Mobile Share plans wouldn't be available for a few months, so it appears that the switch has been flipped earlier than planned — and that AT&T isn't enforcing its new restriction.
AT&T hasn't made a public statement about this, and we've seen conflicting reports on various forum posts and on Twitter as to whether this works or not, so this doesn't appear to be a full rollout of FaceTime over cellular to all users. That said, it's worth a shot — we've found that you'll want to reboot your phone first before trying to make or receive any FaceTime calls. While this is certainly exciting for the users who now have access to FaceTime over AT&T's network, it's also another example of how AT&T's somewhat arbitrary requirements are making a confusing situation for its customers, who all should have access to the same services regardless of their data plan. We've reached out to AT&T for a comment and will update this post with anything else we learn.
Update: And just like that, reports are coming in that AT&T has disabled FaceTime those on unlimited data plans. We can independently confirm that, while it worked just moments ago, we're now unable to place video calls. AT&T hadn't yet acknowledged today's supposed expansion of FaceTime so it may well have been an error on yhr carrier's part.