City councillors were barreling toward the finish line on redistricting, with a plan to vote Wednesday on a map redrawing Boston’s political boundaries. But a last-minute complaint from South Boston groups of an Open Meeting Law violation caused them to hit the pause button.

Most of the 13-member panel met in multiple working sessions early this week to haggle over which precincts, the building blocks of the once-in-a-decade process known as redistricting, go into which of the nine Council districts.

Liz Breadon, the redistricting chair and councillor for Allston Brighton (District 9), intended to bring forward a final map for a vote at Wednesday’s Council meeting.

But after the meeting began, Breadon said they are waiting for the city's legal department to draw up a response to the Open Meeting Law complaint, and the vote will instead take place Wednesday, Nov. 2.

The complaint, first reported by the Boston Herald, alleges that enough councillors met without public notice to constitute a violation. The three events in the complaint were an event led by NAACP Boston and other advocacy group at the Bolling Building in Roxbury, a press conference outside City Hall and a community meeting in South Boston.

The City Council has a history of violating the Open Meeting Law, including a guilty plea in 2008.

The redistricting process has largely revolved around shifting precincts between South Boston-based District 2, Dorchester-based District 3, and District 4, made up of both Dorchester and Mattapan. Over the last decade, South Boston has seen a population boom, while Dorchester has lost population, requiring councillors to redraw the boundaries while paying attention to the federal Voting Rights Act.

A redistricting map backed by the Boston branch of the NAACP and other advocacy groups is said to have at least seven votes for approval, and Breadon has used it as the jumping off point in the working sessions.

Breadon has said a year is needed between the map being passed into law and next year’s municipal election. She also noted that candidates must live in their district a year before the election. The next municipal election is Nov. 7.

Dorchester Councillor Frank Baker (District 3) has balked at the prospect of breaking up the Neponset area’s precincts between Districts 3 and 4, and instead sought to keep all of Ward 16 within District 3 in a bid to put almost all Dorchester-based parishes in his district.

On Tuesday afternoon, Baker reiterated his preferences, frequently interrupting Breadon. Toward the end of the working session, Breadon apologized for interrupting Baker but indicated her interest in winding down the meeting, since councillors were going over the same points.

Baker said that “shows this process has been totally stacked against me.”

“You cut me off in the middle of my statement,” Baker added while interrupting Breadon again.

At a previous working session on Monday, City Councillor At-Large Michael Flaherty asked Breadon if the City Council could get its own legal analysis, since it has largely depended on City Hall’s legal department for that. Flaherty noted that the legal department answers to the mayor’s office first.

Breadon said that in past redistricting cycles, councillors had a budget and could tap its own attorney. But there is no budget this cycle, according to Breadon, who became chair nearly 60 days ago when City Council President Ed Flynn of South Boston(District 2) removed Hyde Park Councillor Ricardo Arroyo (District 5), who was in a heated and ultimately unsuccessful campaign for Suffolk district attorney.

On Wednesday, councillors turned to other topics after Breadon's decision to delay a vote until next week. One topic was Councillor Kenzie Bok's proposal for a pilot on waste containers, and councillors, one after the other, rose to speak in support of a hearing, noting the city has a problem with the creatures drawn to the trash bags that some neighborhoods use, rather than containers with led.

Baker also rose in support of a hearing. "A uniting theme here," he said. "Rats."

This post was updated Wednesday afternoon.