Planning trip overseas, where to send notification letter

[hasb1901]

Hi,
my file is at local office in Montreal, test on June 11, and I am planning a trip of 6 weeks overseas, I heard that I should send by mail a notification letter but I am not sure where Sydney or Mtl ?
if it's Montreal is it the same adress I received on test invite ?

Regards,

 

[chakrab]

you can call CIC and let them know.