Running

(btw, truemilk, depending on which Garmin you've got there's a reset function (I think my Forerunner you hold down two buttons and the bezel) which'll be in the manual. Always clears mine when it freezes, and it boots straight up into working normally again)

Yep, found out this morning trying to google for a solution :(
In the end I didn't miss it too much to be honest, I enjoyed that distance for the first time and probably it was better this way. I'll remember for next time the fucker fucks itself up though.