That was quick

Maybe not the shortest orchestral strike on record, but likely close to it:

They entered the negotiating room in the Chicago Symphony Association’s lawyer’s office at 2 p.m. Monday, and by about 6:45 p.m. a tentative agreement had been reached in the Chicago Symphony Orchestra’s first musicians strike in 21 years.
The orchestra announced shortly before 8 p.m. that the CSO musicians and management had reached an accord for a three-year collective bargaining agreement, to take effect retroactively on Sept. 17. The previous contract expired Sept. 16…
As for the negotiations, which took place at the DLA Piper law firm on North LaSalle Street, [chair of the Orchestra Members Committee Steve] Lester said, “Both sides showed a willingness to bridge gaps.”
“This was an extremely difficult process, and it took hard work on both sides, but we’ve reached an agreement we can live with,” said bassoonist William Buchman, who was on the negotiating committee.

I find short strikes harder to interpret than long ones, which are generally about differences between the parties that are truly unbridgeable until both feel considerable pain. Very little movement is likely over the course of one afternoon from either side. But, if the parties were that close before the strike, it’s reasonable to ask why  that small gap couldn’t have been bridged without a strike.
In those situations, it’s often not just about the proposals on the table, but how one or both parties feel they’ve been treated by the other side. If the musicians felt that management had adopted a “take it or leave it” stance without going as far as they could have, a strike could feel justified simply to make management understand that the musicians wouldn’t automatically take it – which is to say that strikes can be as much about the process as about the deal itself.
That’s not to say that’s what happened in Chicago, of course. But whatever happened, it’s good that neither side is sounding triumphant about the result and that the CSO will be back at work. Another long strike would not have been good for our industry.