I believe that this is new since COVID as I never recall having anything called before disembarkation (although we usually have later dining, so we aren't usually leaving the ship until later), but I don't think it's tied to CC status. It's definitely tied to the colour of your luggage tag, and I suspect that's more about the location of your stateroom than loyalty status.
We had
DCL transfers to WDW last September and they wanted us on those buses at 9 am I think. We were at our hotel well before 10:30 and I think our hotel was the last stop of four. So you don't need to disembark at the crack of dawn to get to MK for a reasonable hour. The major downside of doing express walk-off is that the lines in the ship go all the way down the hall which also means that the line for customs is crazy long. As far as I remember, no one asked what colour our luggage tags were when we disembarked so they don't really police it. And if you have your luggage you can disembark after the main walk-off line without an issue. That would give you time for a decent breakfast, not too crazy lines and still get to MK before 10. You'll definitely get there by 11 because they kick everyone off the ship by about 9:30!