Soon, that is in a few hours, the next iteration of iOS will be released, and that brought back one issue to my attention which I had during the last large update to iOS5.
Then it happened that after the upgrade, even though Google Authenticator continued to work just fine, the generated codes we’re not accepted once I wanted to log into my account. If I remember correctly I received a timecode/timezone error or something along these lines. I could fix this by re-installing the application followed by re-registering it via the QR code in the account/security settings in my Google account.
As the latter was easily done, it would have a been a mess if I wouldn’t have been able to log into my account. To be on the safe side, it seems to be useful to make sure to have access to the Google account and have the backup codes available (or at least the 2 part authentication via SMS 1) before upgrading the OS.
Maybe it will not even be necessary this time, but it sure can’t do any harm to play it safe and avoid a lockout this way.
After upgrading my iPhone this luckily didn’t happen this time again. So hopefully it did not happen for you either.