Hi Matt
As far as I know the PR applicant is supposed to send/give the application to the sponsor who then mails everything off - to CPC Mississuaga.
After the person you are sponsoring has filled out all the sponsorship, immigration and region specific forms, they must send them to you with the supporting documents.
Once the all forms are properly filled out and all supporting documents are gathered, you must send the complete application kit to the Case Processing Centre.
Case Processing Centre – Mississauga
P.O. Box 3000, Station A
Mississauga, Ontario L5A 4N6
If you do not send the sponsorship and immigration applications together or these are not completed correctly, the Case Processing Centre will not process them. They will return the applications to you (the sponsor.)http://www.cic.gc.ca/english/information/applications/fc.aspI would presume London will send the application back to you.
Not sure what the process is for you to contact London - you can fax them or email them but there is no tel. number. You may want to give a shoutout on this board to PMM - he knows so much.