Yes you have to take a complete new connection and you will be alloted with a new ID.
I did the same, firstly there is Official Tata Play Service Centre / Consumer Centre in my area and I asked them that I don't want ODU just need COMPLETE Box only (with HDMI, Remote etc.) So they were saying in 400/- less we can give you Box with 4000/- balance.
But I rejected this because in 3600/- from Amazon I was getting complete new connection with 4000/- balance.
2nd I visited my local dealer he was giving 600/- (3400/- me 4000/- balance) but I told him about Amazon offer
then he gave me in 3100/- with 4000/- balance.
Try to take Binge box (with all accessories of box) in 5100/- with 6000/- balance otherwise on Amazon you are getting Complete new connection (with Dish Antenna) in 5599/- with 6000/- (pic below)
*BUT DO CONTACT AMAZON SELLER IF YOU WISH TO OPT FOR IT
Also remember I was already having unused new Tata Play Antenna and cable.
If you want to use same existing dish antenna then you have to purchase Tata Play Dual Port LNB and wire.
Wire cost in Tata Play is 12/- per metre and 8/- per metre in Airtel ( From Authorised Airtel Service Centre).