White House Communications Director Bill Shine is leaving the Trump administration and heading to help out Trump’s reelection campaign, the White House announced Friday.Shine, a former Fox News head honcho who left after a series of sexual harassment scandals rocked the network, joined the White House last July and quickly emerged as a key behind-the-scenes player in Trump’s orbit.

He played a top role in messaging around the government shutdown as well as helping to handle the swirl of investigations threatening the White House. In a tough environment with an uncontrollable president, Shine stood out for helping to instill a bit more order in a chaotic White House. But in recent weeks he’d been seen at fewer events, a sign that he might be on the outs with the mercurial Trump.

“Serving President Trump and this country has been the most rewarding experience of my entire life. To be a small part of all this President has done for the American people has truly been an honor. I’m looking forward to working on President Trump’s reelection campaign and spending more time with my family,” Shine said in a statement distributed by the White House.

His departure to become a senior adviser to Trump’s 2020 campaign shows how laser-focused Trump is on reelection, though it’s unclear exactly what spurred Shine’s sudden resignation or why the announcement was made without a replacement lined up to fill his position.

“Bill Shine has done an outstanding job working for me and the Administration. We will miss him in the White House, but look forward to working together on the 2020 Presidential Campaign, where he will be totally involved,” Trump said in a statement. “Thank you to Bill and his wonderful family.”