why come ebery time...

If, in the course of a busy day, I ask someone to give me a slow bell between cargoes loading or discharging close to our last port, so that I can prepare paperwork, file paperwork, take soundings, plan the next job, take a leak and maybe prepare the cargo program for the next evolution, I get rolled eyes and a laundry list of excuses as to why we must go at Ludicrous speed (Eleve11nty!!) to ensure that no one is prepared to receive us at the next dock or ship when we arrive and drift and blow the whistle for attention for 20 minutes.
BUT, when the phone calls start stacking up like 747's at JFK, and I've got everything humming on our end, pumps screaming at max, PLUS made room for a lube oil tanker to raft onto us and pump his cargo over the top of our deck, after I get everything prepped and readied for back-to-back-to-back cargoes, and have spent 5 hours doing 8 hours' work, I get a phone call "Never mind, the next load just backed up 12 hours."

Why the hell don't they let me know 5 minutes before we sail? How does someone go from "We'll be done at noon" to "Oh, 0400 now." in the course of an hour?
Grrr.