Unfortunately it's one of the few issues with Android.
Dev's are looking at a way to upload everything off the phone, update and wipe it and then reload content back on, but, at the moment it's taking hours to complete this process....
There are apps that can help with complete phone back ups to ease some of the pain but as long as you don't mind re entering login details and you have your personal files on a cloud somewhere it's not too bad a job to do.
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion. This is not Customer Service so we are unable to help with account specific issues.
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