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I believe a lot of people waiting from the last week of August and first week of September.
I am waiting since September 3

Has anyone heard something from Montreal? Why it is so frustrating
I'm waiting fee rom the first week of October.
 
Just talked to an agent and based on what she said the priority for the people with copr date of expiry mine is July 2024
 
It's not recommended. But if you must, you can. Reply to the portal 1 email again mentioning the date you're leaving and the date you'll be back. This will delay your eCOPR further.
Yes. But you cannot re-enter on a visa if you are given eCOPR while abroad. You can enter on an eTA.