I spoke with a passenger on the flight, who was flying in Suites, and the information they were able to snag from the HYD station manager was that the A380 was flying on a single engine for around 80 minutes.

A fault occurred near Visakhapatnam, but because that airport can't land an A380, they continued onto HYD.

Some time after the fault was detected, passengers were informed that they would be diverting to HYD and would have a "normal landing".