That original plan was proposed in order to save the city approximately $1.5 million, in a year that saw an $8.1 million budget gap.

Facing criticism and protests outside City Hall, Curtatone opted for what he called a “hyrbid” plan that calls for 28 positions being filled by the city’s civil service employees and two schools being controlled by AM-PM.

The school custodian’s Chief Shop Steward, Peter Blaikie, said the announcement took the union by surprise. The union, which has already filed an unfair labor complaint with the state, will be filing a new complaint that the mayor is violating civil service law by firing some employees while also filling positions from a private firm.

“The mayor saved 28 jobs,” Blaikie said, “but if you broke the law doing it, how good is that? It’s ridiculous.”

Blaikie also said discussions held the weekend before the budget was approved were supposed to be off the record, in preparation for a formal proposal, and that Curtatone saying the talks were at an impasse strengthens the union’s case.

“What he did was basically illegal,” Blaikie said. “The terms and conditions [of the new plan] technically don’t exist.”

The city’s legal department would not comment on the litigation.

Meanwhile, a strike is not in the cards. The custodians who were not laid off are expected to report to work. Blaikie, who had been on the lay-off list, will also be returning to the job after a retirement left an open position.

“You have to work now, grieve later,” Blaikie said. “What [Curtatone] did was wrong, but that has to be settled in a court of law.”