Buckle up: There are at least six more Boston Callings on the horizon, all coming to Government Center. Boston Calling Music Festival, which closed its fourth run in two years at City Hall Plaza on Sunday, September 7, will continue to be a two-part pillar event for the city. The music event has locked down dates at City Hall Plaza in both May and September through 2017, City Hall Press Secretary Kate Norton told BostInno in an email.

This is great news for Boston. In its first two years, Boston Calling has become a standout music event for the city, which lacked a music festival of this size before Boston Calling’s premiere in May of 2013. But it squashes hope that the festival might migrate somewhere grassier and more suitable for spending three nights and two days watching live music on our feet, at least for the time being.

A week ago, about 45,000 people flocked to City Hall Plaza over the course of a weekend for the September 2014 festival. Boston Calling has always attracted both internationally headlining artists alongside hometown representation, but this festival arguably charted the most diverse lineup to date, with headliners and performers including Nas and The Roots, The National, Lorde, Childish Gambino, Neutral Milk Hotel and The Replacements.

Still, ticket sales moved slower than they did for the May festival, despite the knockout lineup and the festival’s new collaboration with the annual Samuel Adams Octoberfest, which happened simultaneously at City Hall Plaza over the weekend. The sluggish pace of sales is something that Crash Line Productions Co-Founder Brian Appel attributes most of all to timing.

“It’s hard to say exactly why ticket sales didn’t mirror what they did in the May festival; you can hypothesize that it’s the time of year,” said Appel in a phone call with BostInno. “You can say it’s festival fatigue from an entire summer of festivals, and just people being generally distracted in September as they’re coming back to Boston.”

Regardless of any end-of-summer fatigue that tempers September ticket sales (Appel said that while selling out is a goal, it’s not the only “bar of success”), the latter component of Boston Calling isn’t going anywhere for now, as the dual-year booked dates confirm.

What will be different next year, however, is the booking agency that recruits the bands and artists making up each festival. Since Boston Calling’s inception, Crash Line has partnered with The Bowery Presents in order to acquire talent for the lineups, as well as manage the box offices and consult on other festival operations. Now, Crash Line will part ways with Bowery as its booking agency. Appel said they’ll continue to work with the company on “different facets of the festival,” the details of which are still being finalized.

As the booking agency behind Boston Calling changes, we also learned that the festival team toured a different venue – one outside the city limits. A source told BostInno that earlier this year, Boston Calling looked into the field along the Mystic River at Assembly Row, the new development that celebrated its grand opening season this year in Somerville.

Appel declined to comment on the venue tour, and it’s unclear whether the Boston festival will dabble in the Somerville area in any capacity, be it for the Boston Calling festival we’ve come to know or for a different event altogether. (This summer, Boston Calling branched out by hosting weekly Block Parties in Dewey Square.) For now, though, no switch to “Somerville Calling” is on the books; Boston Calling has made its plans to stay put in City Hall.

Starting next year, however, the music heard over the two Boston Calling weekends may take on a different tune without Bowery Presents involved in booking. Crash Line has decided to bring on an in-house talent buyer to work full time for the company.

“It’s something we’ve wanted to do for a while, and we feel it’s important that we have someone full time dedicated to the booking process,” said Appel.

Bowery Presents is a booking agency based in New York, and they launched a Boston chapter in 2010. Here, the agency books bands for Great Scott in Allston, The Sinclair in Cambridge, and Royale in the Theater District. In the past, the company has been credited for the rise in both mid-size music venues as well as the indie rock genre, the latter of which is reflected in previous Boston Calling lineups.

The shift in the festival’s organization can be considered a setback for the growing booking agency as they build their Boston presence; but it’s not clear what it will mean for the future artists and headliners of Boston Calling. Bowery Presents’ Boston’s Head Talent Buyer Josh Bhatti said in a phone call that he doesn’t foresee a big change coming to the model of the festival.

“It’s been two years, but four festivals in, it’s been successful, so the model itself has worked. I would be surprised if it made a dramatic shift. It’s worked, and it’s proven a winning format,” said Bhatti.

It’s true that since its inception, Boston Calling has nabbed current headliners and big-name artists to play City Hall Plaza and appeal to a wide variety of audience members. What future lineups will come to Boston Calling, however, remains to be seen, and heard.

Images via Hilary Milnes