UniqueIdentifier method of UIDevice

As of 1st May the uniqueIdentifier of UIDevice is no longer valid.

I am having issues submitting an app that previously was fine before that date. While not prescriptive Apple’s submission process seems to be overally aggressive and I can’t for the life of me find the solution.

Its a bit left field but would iPhoneSettings_get_uniqueIdentifier be causing it?

I am on Unity version 3.5.7f6