First come first served? Not up to the driver

Had it with one of Jenkinson’s recently. Process at this site is park outside, hand paperwork and phone number into office an await the call for you to come in.
My phone rang before I’d even got to back to the truck so drove straight in and before I’ve even screwed around in the yard he is charging over face like a tomato arms flailing.
Apparently I’d “jumped” the queue but yard worker reminded him who’s in charge and he’d best return to his motor if he wants in at all. Turns out what I had was going in the load he was taking.