Updating the 75c with Replay mode will most likely cannibalize the 250c sales a bit, so I understand that Evolv would want to hold off with an update until the diehard fans buy their new units.
But, they already said in multiple videos that Replay is coming to the 75c and shot themselves in the foot. It would make sense for them to release it soon since they already made a PR move that would limit the sales of their new chip and devices.