Exactly same question from me.
It is a Day train , and they are making RSA with Night Train.
Already it is messed with Mangalore Exp, and hence Mangalore got 2 Seating coaches which is not necessary / useful for night train. Now again cholan makes RSA with Rockfort and Pandian.
We need atleast 5 2S and 5 SL coaches for cholan express, mostly...
more... need as separate coaches for cholan alone. Am praying when will cholan will have RSA with pallavan and vaigai. Similar coaches only we need in cholan express.