Isn't it the same for the US? Strictly speaking, the F35 is a nuclear capable bomber (same for F18). So if it's not a nuclear escalation for the US to use them against China, why would Chinese ballistic missiles be a problem? Of course the American logic is that it's ok for them to hit others but it's terrorism for others to hit them. Things become dangerous when the American government actually starts to believe that.hmm, I wouldn't want to send DF-27s. Once you have missiles going that far, countries are going to have a hard time discerning between conventional and strategic tipped missiles. Don't even think about hitting west coast with ballistic missiles.
So what can the PLA rocket force do to avoid nuclear escalation? Maybe a salami tactic is best. If the US intervenes in Taiwan but doesn't bomb the mainland, then China won't need to strike the continental US but can attack Guam and other minor islands. The US government might overreact and start a first strike if they see a few dozen missiles headed for California. They won't risk nuclear war if the target is obviously military and has a very small population. If American planes bomb the mainland, then China can slowly send missiles closer and closer to the continental US. It might be ok to announce a target area in the ocean first and then demonstrate to the world that you can hit that point accurately and that the missile wasn't nuclear tipped. Then just move the target area closer to the coast. Boil the frog slowly.