AppleInsider is citing “those claiming knowledge of the matter” who say that a future iPhone software update will enable new AT&T specific features.

These two rumored features are said to be a “collaborative effort between AT&T and Apple based off customer feedback.”

• Overage Alerts would send a push notification to your iPhone when you are in danger of exceeding their monthly anytime minutes.
• New voicemail options would allow a user to  disable the custom voicemail greeting. The same feature would also allow iPhone users to bypass voicemail greetings and other automated instructions when placing calls to AT&T users.

To reiterate, AppleInsider cites sources “claiming knowledge of the matter,” this indicates that AppleInsider is unable to verify whether or not the source would actually have knowledge of the matter, only that they claim to.