Can't restore iPhone 6S to latest iPhone 5 backup

My iPhone 6S came today. I dutifully backed up my iPhone 5 to iTunes, as you can see here in the list of backups:

("Mattress" is the name of my iPhone.)

Great. So I set up my iPhone 6S as a new phone, so I could update the software to match what is installed on the 5. And then I went to restore the backup from today, and:

Where's my backup from today? Why can't I restore it to my new phone?

A clue: July 10th, the date of the backup I can see, is the day I installed the iOS 9 beta on the old phone. Registering the 6S for the beta program hasn't solved it, and neither has deregistering the 5 and creating a new backup.

I'm going to assume your iPhone 5 is running the latest beta, which is iOS 9.1. This is newer version than iOS 9.0.1--the latest non-beta release, and the version your iPhone 6s is running, according to your screenshot.

A backup can only be restored onto a phone running the same, or a newer, version of iOS.

So, if my initial assumption is correct, you'd need to pick one of these options:

• Restore from your July 10th backup--it's clear you'd prefer not to do this.

• Downgrade your iPhone 5 to iOS 9.0.1, and then create a new backup which should then be restorable. (Is this even possible? Perhaps by restoring your iPhone 5 from it's July 10th backup... which is no better than above.)

• Wait until iOS 9.1 is officially released, and then restore from this backup after you have upgraded your iPhone 6s to that new version (who wants to wait that long?).

• Upgrade your shiny new iPhone 6s to the current 9.1 beta release and then restore from the current, missing, backup, which will hopefully become available as the iOS version numbers will now be compatible.

Since you have your iPhone 5 with data intact I would do the following things:

1. Verify the iPhone 6s is at the same or higher version of iOS than the iPhone 5.
2. Remove all restrictions and configuration profiles. These are typically parental controls, beta and enterprise app configuration profiles, Xcode configuration profiles.
3. Open the App Store and update all apps. This is most important and eliminates a bug that is known where App Slicing (a.k.a App Thinning) causes restores to fail when you restore a backup to a new device type.
4. Power off the phone
5. Power it on and double check all apps are updated (or delete offending apps that are not updating or appear hung/repeat updates).
6. Back up the "up to date" iPhone with confirmed non-sliced apps installed.

If that fails, I would back up the Mac and then delete all iTunes backups of all devices. A reboot of the Mac wouldn't hurt here.

If you can't restore from the cleaned iTunes backup, the last thing I'd try before calling support is to set up a new user account on your Mac. Sign out of your current user and try to use the new account and iTunes to make a clean backup of the iPhone 5.

Sorry I don't have a precise "fix" - but these are the troubleshooting steps I've done during the beta process and today to help out someone in a similar situation to you. Hopefully we don't have to "go to the mattress" over this dilemma.

If you are running the Beta 9 Profile when did you most recent backup you can only restore if the profile exists on your new phone. I had an iPhone 6 and was running iOS 9.1. I upgraded recently to the iPhone 6s and it would not allow me to restore from a backup that was done on the 9.1. I had to start as a new phone then redownload the beta profile and update to 9.1. Then reset the phone to factory settings and you should be able to restore from the latest beta backup.