Just thought I'd share a datapoint, a few weeks ago at MCO I couldn't print the bag tags at the kiosk until 4h before departure. Today at LAX, I could print it 12h before departure (morning for a night flight) and was able to drop it off. Both flights are domestic and I was platinum both times.
My trip is LAX-SFO-ORD, bags ended up going on an earlier LAX-SFO plane but are loaded onto my SFO-ORD plane.