To refit the cutters for ASW will cost a lot, not only the upgrades but training as well. Maybe they should build those giant cutters with a huge helicopter deck. For ASW missions, the cutters could provide supports for the helicopters. They could also load land-based missile systems or rocket launchers onto the ships. It's essentially a cheap modular design, isn't it?If coast guard ships were to be drafted into navy combat duties in war time, most likely they will be equiped for similar roles of type 056 and type 056A, i.e. coastal patrol and shallow water ASW roles. I don't foresee that they will be deploy for anti-ship roles, thus won't be fitted with any long range anti-ship missiles.
What role that will be given will depend on the displacement of each ship, since CCG possess ships and boats below 200 tons to that above 10,000 tons.
It is also very unlikely those large ships will be retrofitted with any air defense missiles, nor any VLS. The time to refit CCG ships to navy standard may not be much shorted than building a new navy ships like type 054A. The refit of CCG ships requires more than just add a few missiles launcher racks and a fire control radar. There will be systems integration among all electronic suites, re-positioning of sensors to avoid electronic signal interference, re-training of the crew etc etc.
It would be better just to produce more dedicated warships rather than spending time and money on refitting CCG ships to carry anti-ship or air defence missiles to the level of type 054A or beyond..