Hi,
Yes I am using the Sky Sports app and if it helps this is what I have tried so far !
1. logged out of the account and logged back in _ no effect.
2. Turned off iPad and back in again - no effect.
3. Deleted Sky Sports app, downloaded app again from app store and logged in again - no effect
4. Accessed Sky sports on my mac and could view with no problem.
So the problem seems to be restricted to the iPad. As an aside no problem with live tv on Virgin TV Go although can't access Sky sports on that.