I have found the solution to my jetlag issue.
Vasparov, to be exact. Three shots gulped down in a sequential fashion. That got my head pretty heavy last night. Heavy enough to keep me asleep until the annoying beeping of my alarm clock woke me up. But it was a good sleep. I'm delighted I didn't do that 4.30am rise-from-the-dead ritual which I seem to have been doing ever since my return from America. All that sleep is almost worth the price I'm paying now.
Oh my head. My facking - FACKING - head.