Just reached SE for the first time. I noticed that there are two phone numbers: "Air Canada" and "Concierge". When should I use the AC number vs. the Concierge number? And, same question for the two support email addresses.

Is concierge able to help with Aeroplan issues, or do those still need to go through the regular Aeroplan call centre?

Any other tips or useful knowledge for a first-timer?

Thanks!
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