A top general who oversaw the 82nd Airborne Division during the 2021 U.S. withdrawal from Afghanistan was conspicuously left out of a large batch of military promotions approved Thursday by the Senate before it left town until December.

The apparent delay for Lt. Gen. Christopher Donahue — President Joe Biden’s nominee to lead the Army in Europe and Africa and set for promotion to four-star general — suggests a senator is holding the nomination. Donahue was one of nearly 1,000 promotions the Senate Armed Services Committee approved on Tuesday, and senators in the full chamber typically clear the decks of uniform nominees before an extended recess.

It’s unclear which senator might be delaying Donahue’s promotion and why. Such holds can be done anonymously and can still be bypassed by the full Senate, although the votes can eat up floor time.

Touted by the Army as the last U.S. service member out of Kabul, Donahue led the 82nd Airborne while it was responsible for securing the airfield at Hamid Karzai International Airport as Americans and refugees were evacuating the country ahead of the Aug 31, 2021, deadline to leave. A grainy photo of Donahue climbing aboard a cargo plane at the end of the evacuation instantly went viral at the time.

During the evacuation, a suicide bombing at the airport’s Abbey Gate killed 13 U.S. service members and more than 170 Afghans. Though U.S. Central Command conducted a review that found it was not preventable at a tactical level, some relatives of the slain service members, former generals and President-elect Donald Trump have criticized the administration’s policy decisions.

Trump met with relatives of the fallen service members and emphasized their loss in his campaign rhetoric, a move that he coordinated with his pick for national security adviser, Rep. Mike Waltz (R-Fla.). Vice President-elect JD Vance was also vocal about the attack, saying that Trump’s challenger, Vice President Kamala Harris, could “go to hell” for not holding anyone accountable.

In the last few days, there have been warning signs that those involved in the evacuation could face punishment. The Trump transition team is assembling a list of senior current and former U.S. military officers involved in the Afghanistan withdrawal and is considering the possibility of court-martialing them, NBC News reported.

Since 2022, Donahue has led the 18th Airborne Corps at Fort Liberty, North Carolina. He has also led Special Operations Joint Task Force Afghanistan and served as the Joint Chiefs of Staff’s deputy director for special operations and counterterrorism.

Senate leaders typically look to confirm most, if not all, military promotions at the end of a session — and a move to block an officer such as Donahue would be rare.

But officer promotions, which have long been uncontroversial, are increasingly becoming fair game. Republican Sen. Tommy Tuberville of Alabama took the unprecedented step of blockading several hundred promotions of general and flag officers for months last year in a bid to force the Pentagon to overturn policies aimed at helping troops access abortion.