FYI
Those are dangerous waters for a carrier...confined, narrow, not a lot of room to manuever should there be a problem.
I have no doubts that the PLAN would dispatch at least one of their new, heavy DDGs and probably more than one of their newer (Song or Yuan class diesel electrics) subs. Those subs, in those waters are difficult to find, particularly if they are just waiting.
As to the older ROCN (Republic of China - Taiwan) S-2 trackers...they are very old. A updated P-3 has the sophistication to perhaps find a quiet diesle-electric in the right conditions...but this just punctuates how foolish it was (IMHO) for us to take the S-3 Vikings off of those carriers, particularly in their ASW mode.
Some pretty dicey stuff going on here resulting from the Chinese snub in Hong Kong.