C-v, I agree with Keygrip, but will add a few thoughts as well;
I routed overhead Warton with their radar service, which may be weekdays only, but you can go up to Fl155 if you want, whichever way you are going.....the higher ,the better if s/e; more time to pray, write last letters....joking ,of course.
If you are going to wear an LSJ and immersion suit, I`d try them out beforehand, with someone else in the a/c , as they can be cumbersome, especially a `one-size-fits-all` imm. suit, and especially the feet.
Carry a PLB/ELT in one of the pockets on a cord attached to you; if you take a dinghy, it will have to be easily `get-out-able`, hence a little practice.
Should you have to ditch,get your Mayday off early, point at the nearset ship/oil-rig/coast and breathe deeply and slowly..You`ll be fine, don`t inflate anything until you are clear of the aircraft..
You will probably find the flight( ignore ref. to ditching) all goes off easily, and you may feel a `prat` in an Imm. suit, but your conscience and confidence will be clear..
On a day like today ( in Essex) you will enjoy it , seeing the Seven Kingdoms...............
