So after a few days, battery life is much the same. I go to bed with about 55-70% charge left, depending on what I’ve done that day (eg it’s lower if I’ve gone for a run and used the GPS), and how long I’ve been up for!
The updated swimming activity is good, it needs refinements though. It managed to pick out the different sets, but the timing is a bit off, it said I had a rest of a negative figure for one of them. The single most annoying thing for me is the activity app which no longer shows the current hour as darker in the stand graph if you haven’t yet moved. I often used to have a look to see whether it had registered that hour or not, and you can’t easily tell anymore at a glance. (Got to close those rings!!!)