I have a UIFlow program running every 30 minutes, calling an API to update the display, and then going into deep sleep. It's been running about 10 days on the same charge so far. Initial battery voltage was ~4600 (I don't think I fully charged it) and it's currently ~4340. It looks like I'll get a month or more out of one battery charge, which is much better than I expected.
Is there anything I can do to extend this into many months? What is the maximum runtime you've been able to achieve from one charge before it expires, when using wifi?