You'll probably find that the pilot was also an airliner driver, and had forgotten the normal technique for joining the visual circuit.
I was Duty Bod in the tower at Benson once. 4 Bloggses solo in their Bulldogs in the circuit, when someone in a corgi-carrier (no royal on board) announces he is positioning for a straight-in visual join.
"Tell the bugger to join through initials with 4 in ahead", I told the local controller. "But..but...it's the Queen's Flight", spluttered the controller.
"I don't care who he is - the Flying Order Book does not include priority for visual straight-in joins. He can either break off and position for an instrument approach, or fit in with the visual circuit traffic. His choice!".
After being somewhat surpirsed at the instruction, the corgi-carrier duly joined through initials, then completed a tidy run-in-and-break in his BAe146. Later he mentioned the event to the CFI. "Serves you bloody right", said the CFI, "Suggest you read the FOB in future!"