The FCC stopped the informal countdown on July 21, saying that AT&T had indicated it had revised its models to support the merger’s approval.

In a letter, the FCC said it had “received AT&T’s answers to our specific questions as well as AT&T’s confirmation that it believes our record is complete with respect to the models.”

“Our understanding is that, unless specifically prompted by a request from the Commission or the Department of Justice, AT&T will not be submitting any further revisions to the models,” wrote Rick Kaplan, head of the FCC’s wireless telecommunications bureau.

Friday, Aug. 26, is Day 83 of the informal 180-day time frame set aside for the agency’s review.

“We are pleased that the FCC has restarted the clock, and we are confident that the Commission will move expeditiously to complete its review of our merger with T-Mobile,” Bob Quinn, AT&T’s senior vice president for federal regulatory issues, said in a statement.

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