My wife has an iPhone SE, running 10.2. For some reason, the iCloud backup is not working for her. She has the 50 GB account, and is trying to backup approximately 9 GB of data. It will get about 1/3 of the way through the backup, saying it has about 15 minutes remaining, then the time remaining jumps up to 3 hours and it never completes the backup, no matter how long we leave it plugged in and locked. I tried turning off the photos app last night to reduce the size of the backup to approximately 2.5 GB and it still did the same thing. Any thoughts on what we need to do differently to get iCloud backups to start working for this phone? I was trying to back it up before I install iOS 10.3 on it.