Last week, the Cubs announced a seemingly minor schedule change: The final game of a late June series against the Nationals would be moved up a day, at the request of a Chicago city official, and turned into a day-night doubleheader on June 28 to accommodate the neighborhood traffic and congestion as a result of Chicago’s annual Pride Parade on June 29. The Nationals now have a doubleheader to close a seven-game road trip and gain a rare Sunday off day. According to Cubs historian Ed Hartig, the last scheduled day-night doubleheader at Wrigley Field was July 4, 1983.

But since then, I’ve received some questions about the reasoning behind the decision. One of the prevailing qualms: What prevents any city from asking teams and Major League Baseball from moving games for other events, concerts or parades?

While a Chicago alderman requested the change, the Cubs worked with MLB on the change, and the league office ultimately has the final approval on schedule changes. All parties, including the Nationals, were cooperative with the change, according to a MLB spokesman.

Traditionally, requests for events that could affect the area surrounding a stadium are made before the MLB schedule is set and the league tries to accommodate those as much as possible. “However, not all requests can be met, and sometimes we have to adjust,” MLB spokesman Michael Teevan said in an email. So, because this issue arose after the fact, MLB, the Cubs and the Nationals had to alter the schedule in an unusual way.

Changes like this have happened in the past. A three-game series between the Blue Jays and Phillies in 2010 was moved from Toronto to Philadelphia because of a conflict with the G20 Summit, particularly over security concerns. In 2011, a three-game series between the Mariners and Marlins was from Miami to Seattle because of a scheduling conflict with a U2 concert.

The first game of the doubleheader between the Nationals and Cubs is slated for 1:05 p.m. ET on June 28, followed by the second game at 7:15 p.m.