Every zone auguments trains when there is demand and spare coaches. I have seen only SCR giving number of berths made available.
Recently SWR augumented 1 CC coach in MAS-SBC Shatabdi. It just gave at coach level and not at seat level.
Seat level info is like magnifying the information.
SR runs most of its key trains with max 24 coach rake or 23...
more... coaches on permanent basis.