Ok everyone, apple got back to me and this worked. Order of operations is key - I had tried every step below, but not in this order. Hope it works for you, it did for me:
1. Close All Apps on iOS device using the steps in this article:
iOS: Force an app to close
http://support.apple.com/kb/ht5137
2. Sign out of iTunes & App Stores: Settings > iTunes & App Stores > Tap Apple ID > Sign out
3. Reset your iOS device. To reset, press and hold the Sleep/Wake button and the Home button at the same time for at least 10 seconds, until the Apple logo appears.
5. Sign back into iTunes and App Stores: Settings > iTunes & App Stores > Sign In with Apple ID.
6. Go to App Store Updates tab and check if it doesn't display a blank page.