CHICAGO (CBS) — While a deal has been approved and the Chicago Teachers Union has agreed to end its strike, the strain of reaching the agreement seemed apparent on both sides Thursday.

As CBS 2’s Dana Kozlov reported, that is because this was a deal that almost wasn’t.

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Before the announcement, teachers were marching in the Loop amid an unseasonably early Halloween snow, chanting: “Get up! Get down! Chicago is a union town!”

“This has been a very hard and difficult journey,” Mayor Lori Lightfoot said.

Early on Thursday afternoon, Lightfoot announced the Chicago Public Schools would make up five of the 11 school days lost to the teachers’ strike, and classes would resume on Friday. It was not immediately clear how the district would make up the five days.

Teachers had been on strike since Oct. 17, and students have missed 11 days of class. This strike ties for the fourth longest in Chicago history.

And even the announcement that some strike days would be made up and the strike would end could not bring Mayor Lightfoot and Chicago Teachers Union officials together side-by-side.

“I just didn’t feel like doing a celebration lap with the mayor right now,” said CTU President Jesse Sharkey. “That’s not what our members need to be looking at. That’s not what the people of the city need to be seeing.”

The strike was called off after a closed-door meeting on the fifth floor of City Hall, precipitated by Mayor Lightfoot saying the ball was in the union’s court.

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“I’m here all day. I’m going to be working and continuing the business of the city,” Lightfoot said. “If they’d like to have a conversation, they know how to find me.”

When Kozlov pointed out in a City Hall elevator that Lightfoot said she was in her office and willing to meet with him, Sharkey said, “Yeah, well, that’s why I’m City Hall – trying to talk to the mayor.”

It took two hours to work through what appeared to be a last-hour demand from the union on Wednesday – that they would only go back to work if all missed days were made up. It was an issue that seemed, to some, to come out of nowhere as a last-hour goalpost move.

“That’s just simply not true,” Sharkey said when Kozlov asked him about that claim.

Adding a back-to-work agreement is standard negotiating procedure. But it nearly harpooned the strike’s end in this case – and it may cloud City Hall’s relationship with the CTU from this point forward.

“This has been a tense last two weeks,” Sharkey said.

A seven-day teachers’ strike in 2012, and subsequent school closings, permanently strained the CTU’s relationship with former Mayor Rahm Emanuel. But a 2016 strike was averted.

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It is also worth noting that earlier this year, the CTU threw its endorsement behind Mayor Lightfoot’s challenger in the 2019 mayoral race, Cook County Board President Toni Preckwinkle. Some wonder if that played a role in everything that happened the last couple of weeks.