What if China goes for the northern Phillipines instead of Taiwan first?

 When the players don't play nice, expect shocks.   Taiwan has 22 divisions for China to overcome whereas northern Phillipines (Luzon) does not.  Either island mass, once captured, gives a defensible gateway to the open Pacific and the upper hand over Japan      Suggested by Wretchard the Cat.  (The redoubtable Richard Fernandez).  

"If China wants to take over the Pacific its obvious goal will be to knock Japan out of the Quad. From a purely strategic point of view Japan, not Taiwan, is the crown jewel. How best to neutralize Japan? Control Luzon or Taiwan."