So yes this whole pack of batteries is bad... last night it woke me beeping again at 3:45 am, after having a really really hard time falling asleep in the first place. (So much for trying to work on getting into a regular sleep habit).

And no way would I go back to bed just removing it to deal with in the morning (especially after posting here! ) so I had to fumble around at 3:45am to see if I could find another battery, luckily I did have one and was able to get it in and go back to sleep. Hopefully this one will last more than 36 hours.