Another City of Boston official announced their resignation Monday, just prior to when Mayor-elect Marty Walsh will be sworn in as the next Mayor of Boston. This time it’s Boston Transportation Commissioner Thomas J. Tinlin who made it abundantly clear that he will tender his resignation on the exact same day the Mayor-elect’s ceremony is slated to take place: January 6, 2014.

Interestingly, Tinlin isn’t the first public authority to ship out of Boston City Hall as a number of constituents have, and possibly will continue to, follow suit.

“After much reflection, I have decided to move on from BTD effective on Monday January 6, 2012,”  Tinlin wrote in a letter to his City Hall colleagues according to the Boston Herald. “I cannot begin to tell you how much I have enjoyed my time here and our time together. We have had celebrations and tragedies, and through it all we have stuck together, had each other’s backs and been a true team.”

It’s unclear at this moment as to whether or not Tinlin had some kind of disagreement with Mayor Tom Menino’s successor, but one would actually think quite the contrary. Walsh as been vocal and adamant about improving the state of Boston’s entire transit system, expressing his intent on keeping the MBTA open during later hours and his support of its pilot program to do just that starting next year.

Tinlin follows the likes of former Boston Police Commissioner Ed Davis, Fire Commissioner Roderick Fraser, Chief of Personnel & Labor Relations John Dunlap, Chief Information Officer William Oates and Chief of Human Services Daphne Griffin, all of whom have taken jobs in other positions not in the mayor’s cabinet.

Keep in mind, too, that Boston Public Schools are also still without a superintendent, though the Walsh administration likely has personnel on tap to fill that, as well as each of the aforementioned positions.

And rather than look for a beef between Mayor-elect Walsh and his peers, it’s important to realize that perhaps we’re witnessing a harmless regime change, a commonplace occurrence that takes place when one knows they may be replaced by the incoming chief.

BostInno reached out to UMass Boston Associate Professor and Chairman of the Department of Political Science Maurice Cunningham, an expert in Massachusetts politics and contributor to the political commentary site MassPoliticsProfs, to see if perhaps there is an underlying issue between Walsh and sitting city officials.

“It is very common for a transition,” Cunningham began in an email to BostInno. “A new executive understandably wants his own team in there. Some officials may communicate a wish to stay on, and sometimes they do. Others may simply see the mayor desires to go in a new direction and resign. Others may be tired — Menino was in there 20 years and some of his folks have served a long time too.”

Concurred Peter Ubertaccio, fellow MassPoliticsProfs contributor, Director of Joseph Martin Institute for Law & Society, and chair and associate professor of Political Science & International Studies, “These resignations are good and useful: City agencies now have a new boss and the beginning of a new administration, particularly after a 20-year incumbency, is the best time for an incoming mayor to put his stamp on the city’s bureaucracy.”

Walsh will be sworn in as Mayor on January 6, 2014, on the campus of his alma mater, Boston College. In the meantime, be sure to check back with BostInno for the latest news on Walsh’s transition and potential candidates for his new cabinet.