1. For 1Ac Booking Earlier or after doesn't give guarantee for getting a Coupe.. At time of Chart preparation, seats are allocated unlike case of other classes where you give preference and get that seat.
2. Chart are generated by the Computerized system. I don't think manual intervention is done by any person, he just press Generate Chart Button.
By Chap i guess you are talking about TTE who gave the coupe to you.