After AT&T had to delay enabling WiFi calling on iPhones — a move it was expected to make, but didn’t, with the release of iOS 9 recently — the carrier is finally getting the go-ahead it needed from the Federal Communications Commission to roll out the feature to its customers.

The phone company was waiting on a waiver from the FCC that would allow it to launch WiFi calling despite the fact that the system doesn’t work reliably with TTY — a teletypewriter for the hearing-impaired. An alternative feature known as RTT (real-time text) that does work with WiFi calling won’t be available until 2016.

AT&T says while it’s grateful that the FCC decided to grant its request, AT&T senior executive vice president Jim Cicconi added that it’s still weird that rivals Sprint and T-Mobile are allowed to offer WiFi calling without even asking for the waiver, writing on the company site that “we are left scratching our heads as to why the FCC still seems intent on excusing the behavior of T-Mobile and Sprint, who have been offering these services without a waiver for quite some time.”

Instead of trying to go after Sprint and T-Mobile or opening an investigation and allowing those companies to now apply for waivers, Cicconi says the FCC is basically implying that “that their prior flaunting of FCC rules will be ignored. This is exactly what we meant when our letter spoke of concerns about asymmetric regulation.”

We still don’t know when AT&T will actually launch WiFi calling, but will update this post when that information becomes public.

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