I went to the Apple store to have all the batteries in my iPhone's replaced today and my 6S was the only one to have troubles with the process and for whatever reason came back to me needing to be restored. It won't let me restore the device because it's on iOS 9 and I refuse to upgrade it as that iOS is plenty satisfactory for the device and I have very partial preference to using it. Is there anyway to activate this without updating the iOS or am I out a phone now?