There is ONE main function every thermostat must do to be fit for purpose. Nest failed on that. They deserve to go under as a company.
The whole idea that you can actually save money with them is laughable anyway. If you have a pattern of when you are home and not home, if Nest can learn it SO CAN YOU! Then you can set your 7 day programmable thermostat. You can also turn down your programmable thermostat on a hold temperature before you leave on vacation, while your Nest will have to figure out for itself that you're gone.
The only way a Nest could save anyone 200 pounds a year would be if they previously either had a manual thermostat with a single setting for 24x7, or they had their programmable thermostat set several degrees higher than their Nest keeps the house and they just never realized they would be comfortable at a lower temperature. I used to keep my house warmer, until one winter when I tried dropping a degree a week to see when I felt 'cold' and found I was comfortable several degrees cooler than I had previously kept it. Saves a few bucks and fewer problems with winter dry skin since the furnace isn't running as much.
Can't believe people are still defending Nest after that huge fiasco! Obviously they didn't test their updates very well - it isn't like a PC where there are thousands of hardware configurations! Not sure why would they ever deliver any updates during the winter anyway. Do it in the fall and the spring only. Or hell, even the summer. If you get a bum update in the summer and lose your AC, it can be uncomfortable, but losing it in the winter could mean burst pipes and thousands of dollars in damage! But I guess Nest doesn't care, they have a EULA which they think absolves them from all responsibility. Someday someone needs to test these EULAs in court.