Thanks for all the comments everyone. Things are coming together. I booked my day 2, 8 and test-to-release tests. I had picked out one website (as listed on the UK government page) only to find out they didn't accept overseas payments. Their explanation, when I asked how to fill out for those with a different billing address, was that because they didn't ship outside the UK, they didn't accept payments. I picked out another site - recommended by someone in one of my British Facebook groups - and managed to book through them. They didn't ship outside the UK either but did accept billing addresses from outside the UK.
I walked today. Made the most of the good weather as it's supposed to rain all day tomorrow. Yesterday was very buggy - mosquitoes galore (which I won't miss!) - and I got bit several times despite being covered in spray. Today was the total opposite. I went even more prepared today but the mosquitoes were few and far between. It was lovely out so I spent more time than I usually would. Phone photo below of the lovely reflection and clouds.
I spent the afternoon outside on the back porch watching the birds and their babies. They are so funny to watch. Later I did go up in the craft room for a bit.