Ah, looks like I am not alone with 'easy water damage' issue. I didn't even swim or take it into a bath. I usually took it off while showering. One day I forgot to take it off before I started the shower. So it got a big splash of water on it. Took it off immediately. But it was too late. The watch showed water ingress after a few hours (refer to images attached). But it kept working for two weeks. The ingress pattern changed (to an interesting one ;-)...) but once the battery died, it never came back on. I deliberately didn't attach it to the charger for almost a month. But when I did, it did not respond at all.
Going to leave it the Sun on the window sill for some more.
I've gone back to my chonky BangleJS 1. And after a firmware update, I am amazed at the quality of apps now. Absolutely loving the functionality in the "Recorder" app, supplemented by the "Run" app. Also the AGPS addition is wonderful! I have two of these, so should keep me happy for a while.
P.S. No one supports water damaged electronics, not even Apple/Samsung inspite of their fancy IP claims. So, no I am not expecting any discount, or support on a £40/- watch.
This is just an FYI for people to be extra careful with their BangleJS 2.