Harry Styles performs on The Late Late Show with James Corden on May 18, 2017 on The CBS Television Network.

Harry Styles performs on The Late Late Show with James Corden on May 18, 2017 on The CBS Television Network.  

Terence Patrick/CBS via Getty Images

The One Direction member makes his first appearance on the primarily rock-driven airplay chart.

One Direction's Harry Styles makes his first foray to Billboard's Adult Alternative Songs airplay chart, as "Sign of the Times" debuts at No. 30 (on the list dated June 17).

The song debuts nine weeks after its maiden appearance on the Pop Songs airplay chart (April 22). "Sign" has since risen to No. 12, where it holds for a second week. (1D has never appeared on Adult Alternative Songs.)

Wait: Styles on a chart led by Portugal. The Man ("Feel It Still") at No. 1, followed by at Nos. 2 and 3, respectively, Dan Auerbach and The Lumineers?

It could seem odd to see a boy band member on a rock-centered chart. But given its sound, reminiscent of '70s prog rock, certain programmers are welcoming the song, including Emily McIntosh, program director of KGSR Austin, Texas, which spun the track 32 times in the latest tracking week (ending June 4), according to Nielsen Music.

"I'd be lying if I said there weren't a few raised eyebrows, both inside and outside of KGSR, when we announced we were adding the record almost immediately," she says. "But the word that permeated so many conversations about the track consistently was 'surprise.' Harry surprised us all with a song that shook the conventional boy-band-member-goes-solo aesthetic. And often, that surprise turned to genuine delight."

"Sign," says McIntosh, is a "timeless ballad that deserves the attention of programmers and music fans worldwide, regardless of his history as a [pop] musician and performer."

Other adult alternative stations playing the track high in rotation include KRVB Boise, Idaho (24 detections in the tracking week), KBCO Denver and WMMM Madison, Wis. (23 each). Overall, the song's adult alternative spins for the week mark just 2 percent of its total, with the bulk driven by pop (63 percent) and adult pop stations (23 percent).

"Sign" is also not the only overtly pop-leaning track currently on Adult Alternative Songs; The Chainsmokers and Coldplay's former Pop Songs No. 1 "Something Just Like This" reaches a new peak at No. 15. While it's EDM duo The Chainsmokers' first visit to Adult Alternative Songs, it's Coldplay's 26th, a sum that includes a record 12 No. 1s (a mark that the band shares with U2).

Styles' self-titled debut album bowed at No. 1 on the Billboard 200 dated June 3, earning 230,000 first-week equivalent album units.