Hello,
As i understand via indiegogo updates news. That when HUB is offline (power off) , weather data is stored on AIR and SKY and when HUB is back online (power on), AIR and SKY would send missing data to him. 
Do i have to change some setting or did i miss read information?
for me, I get the last hour re populated OK
but have not seen it work for longer than that?
maybe others can share their experience
same here, in my case I just noticed that it approx restore one hour and half of data in my graph.
Ok…i think that is really not enough…1 hour of data…i was expecting much more…
Put a UPS on the hub and it will store many hours of data. When power returns and you have internet access back, it will upload the data.
Does this still hold true, RE: Data is lost when Hub is powered off? I missed several days of data during a power outage.If the Hub was ON for those several days but Internet was off would it upload all backlogged data for the last several days … when the Internet is restored?
The sensors will only hold a few hours of data so if the hub is not powered you will lose data after that amount of time. Not sure of the exact amount of data a powered hub will hold but believe it is a few days worth. In theory it should backfill the data it holds once internet is restored but last I read a few have had issues with the backfill process.