With its proposed $26.5 billion merger with Sprint on hold, and taking longer than anticipated, T-Mobile US had to throw some serious cash and stock at CFO Braxton Carter to keep him around.

The company filed an amended agreement for Carter’s employment with the Securities and Exchange Commission that keeps him in the employ of T-Mobile US through the end of 2019, 20 days after the first quarterly filing upon successful completion of the merger, or 20 days after the deal falls apart — whichever occurs first.

Carter, a long-time telecom executive, joined T-Mobile US in April 2013 when the company merged with MetroPCS. His future at the company has been questioned since Sunit Patel, former CFO at CenturyLink, was hired six months ago to oversee the company’s planned integration with Sprint.

The amendment and increased payout for Carter is a clear sign the merger is taking longer than expected, explained Roger Entner, lead analyst at Recon Analytics. “It would look so bad if he would leave before the close of the thing,” he said. “If the CFO leaves right before the merger that spells trouble, so they had to keep him in there.”

Regulatory review of the proposed merger is on hold for the third time since it was originally filed with the Federal Communications Commission (FCC). The informal 180-day shot clock is resting at day 122 while FCC staffers study additional information filed by both companies.

Under the terms of the new agreement, Carter’s base salary was increased to $950,000, including other changes to stock-based compensation. Company stock awards for Carter are timed to outcome of the proposed merger, but he may not be the only executive to leave if or when the deal reaches a conclusion.

“All the incentives are in line for [CEO John] Legere to leave after the merger closes, and all the incentives are in line for [COO Mike] Sievert to become CEO after the merger closes,” Entner said. “Mr. Legere has a very nice package after six months if he leaves.”

T-Mobile US has been pushing for the merger to close within the first half of 2019, but that deadline is looking less likely as the FCC review remains paused and as state attorneys generals from a dozen states mount a legal challenge to the merger.