Uncanny that I had the exact same timeframe for getting a replacement; in my undergrad I was doing an ethnography on QS culture and spent about 2 weeks waiting for my UP band to get replaced when it broke, only to have the replacement break a few weeks later. I ended up buying a second band and at one point used each in rotations while the other was in the process of getting replaced. After my fieldwork I stopped bothering to replace them despite them still having some time left on their warranties.