Went for another dawn swim, just before 6:00am. My new glasses came with the most ridiculous steampunk case, looking rather like a canister intended to be sent around an office building via pneumatic tube a hundred years ago. Found that my swimming goggles fit into this perfectly.
Weather beautiful, water freezing and murky. Took three or four attempts before I could submerge without hyperventilating, and when I did I couldn't see beyond my own goosebumps.

Note to self: Remember to go to bed early on Friday and Saturday nights so I get a solid few hours sleep before it all kicks off.