A 450kph limit for the rolling stock is great, but how many lines are actually capable of these speeds? There's only a single line (Chengdu–Chongqing, currently

A 450kph limit for the rolling stock is great, but how many lines are actually capable of these speeds? There's only a single line (Chengdu–Chongqing, currently under construction) which is designed for 350kph, with sections capable of 400kph. Aside from that, most lines are at 350kph - unless I'm missing something.