I was lucky enough to have the Nexus 7 2013 to KitKat OTA fail with the No Command message on reboot. So after trying many of the things suggested in this great group I had to do a factory restore but I figured that wouldn't be so bad since I purchased Helium and had a backup of my device from a few months ago. Imagine my surprise when I tried to do a restore and got the "Back Backup File" message from Helium. Nice.... So I checked online and found that this is pretty typical. Right now I hate Google and Helium because I lost everything for the last two years.