I'm sure that during the time airborne the flight crew consulted their engineering colleagues on the ground and a joint decision was arrived at after all the permutations were considered.
One of which would have been the possible implications to the return service in Shanghai. Often it is the better option to return the aircraft for repair at a main base rather than have it stranded downroute awaiting spares etc.
As is often said, 'nothing to see folks, move along ...'