I may be wrong but recent high level visits and recent trainings with China giving me hints about a real two front strategy.i hope it is true.plan have all the logistic support at Karachi and gwadar.their nuclear submarines frequently visits our ports.they have vessels in indian ocean on almost daily basis.
Unless I am mistaken, these are all tracked.
Nuclear submarines are useless unless China is willing to go all in against India. They are expensive and they are not going to risk their submarines to fire regular missiles.
Btw, there is a reason why India has weaponized Brahmos in multiple variations. Chinese Navy is not coming to help you.
The logistical challenges are a suicide for Chinese Navy.