My understanding of the Cursed Sails crew rotation is that they're on a ten day (4 hour IRL) rotation in each region, and all server times are synched, so if I end up playing from 8pm-10pm each evening, the same crew is always going to be up.
I'm sure I'm not the only one that can't play at 2:00 in the afternoon or morning in order to face a certain crew. If different servers had different rotations, so I had a chance of seeing everything in the few hours I have every couple nights to play, I'd really appreciate it.