Time Sink

No matter how fast you travel, you’ll get there when the DM needs you to. You won’t be late or early, and won’t miss the planned event. And if the ocean voyage takes longer than expected then that one-a-century celestial occurrence will be delayed by a miscalculation or calendar error.

Probably.

Maybe.

Unless your DM is one of those ones who lets time pass if you choose to become distracted and go on side quests. In which case, you might not make it in time after all.

Yeah… better to be safe than sorry and worry a little.