After great difficulty, I found the procedure to get MNP Code for Aircel, Chennai.
It is very easy and the best method to get the MNP Code.
Please follow the following procedure
1) Go to this location given below
Aircel has setup officals to give MNP Code on the spot
Please note : it is in ground floor
Google map link to Prestige Polygon towers : https://goo.gl/maps/PD3X4bVJdSz
2) Both prepaid and postpaid customers can go.
3)If you are the owner of the number, just carry an ID proof(any ID proof(original or xerox will do)).
4)Stand in the queue(5 to 10 minutes).
5)The person will ask for your Aircel phone number.
6)They will check ID proof and will immediately give you MNP CODE within seconds.
Additional info:
Postpaid owners can pay their pending bill in the same spot.
Parking is not allowed inside the complex and it is difficult to get a spot to park outside even for a two wheeler. So, better come in Ola or Uber.
I heard one more location near Little Mount, Chennai does the same.
Google map link : https://goo.gl/maps/PD3X4bVJdSz