According to Preferente (spanish media), China Southern is planning to launch flights from CAN to BCN and MAD next S18 and also launching flights to South America via these cities.
Also Mr. Wu Gonxiang, maketing vicepresident of CZ Group says that both countries are discussing about traffic rights to make success the launch of these new flights.
On the order hand says that CZ could fly 3 times a week with 788.
In my opinion, it could work because both cities have had new routes to Asia during last 2 years and currently are working with high load factors. Today for exemple CX has announced HKG-BCN route from seasonal to year round.