the pirate ship leaves norg every 57 minutes.

selbina<->mhaura is every 16:00 , 00:00, and 08:00

the pirates will attack the boat everytime the pirates departure matches the 00 00 time spot from selbina<-> mhaura. If it matches at 16 they dont attack. if it matches at 08 i never tried so cant confirm if they attack this timeline spot.