you would also be needing a letter from an organization stating that you have done the ground for the ATPL . And according to the CA-9 Annex 14, either the Commanding Officer/general manager - operations/CFI shall sign the form....
Commanding officer - Would only sign it if you are from the forces.
GM- Operations - Would only sign if you are with the airline.
CFI- I don't know but i asked a lot of CFI's and they say, they cannot sign for ATPL as none of the flight schools have an approved Ground School for ATPL.
so i think the only option is that you can write ATPL only after you join an Airline. I myself have tried to find out a lot about it and even got my form rejected because there was no course completion certificate.