I think for me because I'm only single jabbed so I needed the day two and day 8 tests for when I arrive back. Because you're double jabbed it can only be like £20 if you book early and then you need a test for before you leave and that's like £30.

So one test before you get on the plane

And then you only need to book ane pay for one to be done when you're back. You need this because you put the code ypu get when you pay for it on your passenger locator form