If you are thinking of spending $200 - $240 on a
DCL bus, why not just book the Minnie Van resort-to-port transfers? It's $240, can accommodate up to 6 guests plus your luggage and you can schedule your pick-up for whenever you want. It keeps you in the Disney bubble and they drop you off at the curb in the terminal (inside security).
We took the DCL bus once from BWI a few years ago - never again. It picked us up late morning and then went to AoA to pick up more passengers who were late getting to the bus so we had to wait for them. It was such a waste of time. We now use a private car service (Park Avenue Limo) for all ground transfers in Orlando. The last time they took us to the port from YC, they even knew a back way to get to the DCL terminal, circumventing the standstill traffic that was trying to get to the area.
IMHO, if you are going to spend that kind of money on transfers, I would seriously consider the Minnie Van or a private ground service. The DCL bus is just a bus.