Early disembarkation has nothing to do with your Captains Club status or your stateroom category of not in a suite.
Walkoffs, those who can take all their own luggage with no assistance, starts at approximately 7 AM.
BUT since you will be wanting them to take your luggage the night before, and issue you a number, they will probably start calling them around 7:30 so ask Guest Relations for the lowest possible number tag.