Actually, we are using DCL buses and had to pick an arrival time during our on-line check in. We are flying in the night before and staying at the MCO Hyatt so I'm not sure if that makes a difference.
I'd read on here that if you are taking DCL transfers that you wouldn't need to pick a time so I called DCL and explained that we were taking the DCL bus so how would we know what time and the CM told me to just estimate at what time we thought we'd get there.
Don't think she realized what I was saying - we don't know what bus we'll be assigned to. Anyway I just picked the earliest time available. Hope it doesn't prevent someone else getting it if we get stuck on a later bus.