Well, I've handed in the aforementioned notice, and it went as well as could be expected. In fact I think the boss was quite relieved - me leaving saves him some money and the books aren't exactly full of orders right now.
Now I have the (for me) nightmare of organising myself home in one piece, and with as much as possible of my vast fortune intact. I hate this part...
Thanks to all who sent me birthday wishes. The best birthday present would be a time-travel gadget to bypass this week.
My flight home (ahhhh) is booked for May 8th. Motorbike service is booked and the bike will be ready for me. Can't wait.