Still, there's no reason they can't start that cascade soon enough to save employees the commute. For that matter, you don't even really need that chain of command because corporate could easily just automate sending out a mass text to all affected employees once there was no more opportunity for sabotage. That would likely leave them scrambling to contact their managers as needed until they went far enough up the chain to get an authoritative answer, but at least they'd save a commute.

I don't doubt that front-line managers are just as out of the loop as front-line staff are, but somebody knew this was coming at least a few days in advance. To do nothing to communicate it in a way that limits the inconvenience for front-line employees is just plain inconsiderate.