As O.A.R. celebrates 30 years since the group’s formation in Rockville, Maryland, frontman Marc Roberge says it feels like both a long time and no time at all.

“It has gone very quick,” Roberge, 47, says via Zoom from the O.A.R. tour bus. “I honestly feel like we’ve had a good bit of the apple, multiple times, and to say it went by in a flash would, I guess, devalue those bites a little bit. I really do try to lean in and remember everything, but it does feel like it’s happened in section phases … and is still going like that.”

Roberge and bandmates Chris Culos, Richard On and Benj Gershman (now a part-time member) released an album, “The Wanderer,” before heading to Ohio State University, where they met saxophonist Jerry DePizzo. O.A.R. has released 10 more albums since then, including the upcoming “Three Tinted Windows,” which comes out Sept. 18 and has been preceded by several singles.

The group also worked with rapper B.o.B. on the song “Champions,” supporting the 2012 U.S. Summer Olympics team, and performed at the opening ceremony of the 2015 Special Olympics World Summer Games. Last summer, the band teamed with the Washington Nationals baseball team on the anthem “Our Diamond, Our District” for a new uniform reveal. It’s also a principal partner in the Oceans Calling festival in Ocean City, Maryland, which started in 2023 and takes place Sept. 25-27.

The story’s hardly over, but at this juncture, Roberge feels O.A.R. is in “a pinch-yourself moment. You can call it overtime. We already feel like we’ve accomplished what one percent of bands get to do, so now we’re just in a gratitude phase at all times — and it’s only getting bigger, which is the craziest part.

“It’s not even about wanting to prove anything, or feeling like we have to. It’s just about being ready for when you get phone calls, and we get so many phone calls for interesting, fun things. If we were not prepared to do them, we would have to say ‘no,’ but we just say ‘yes.’ That’s what’s best about this phase. We’re always working and being ready. There’s no resting on any laurels.”

O.A.R., Gavin DeGraw and KT Tunstall perform at 6:30 p.m. Saturday, Sept. 5, at the Michigan Lottery Amphitheatre, 14900 Metro Parkway, Sterling Heights. 313-471-7000 or 313Presents.com.