I received the following reply from AC regarding my claim:.it seems that this is the standard reply they send as opposed to providing a details on the root cause of the delay. They did include in their response that " IF you would like us to take another loo, let us know". I wrote back on December 29,2022 requesting additional information the route cause for the cancellation (their initial email had said "technical" issues) but have not had a response from them.
Based on some other cases I am aware of, it seems that this is a standard response from AC to give a goodwill and call it a case closed. I am leaning towards pursing this further because I do think (don't have any concrete information to prove anything) that it should qualify for a full compensation under APPR.
Am I wasting my time and just should accept or have others taken it further with positive results!!
I had another 10 plus hour delay since this claim and got the exact same response from AC...

Thank you for contacting us about your request for compensation due to your flight disruption.

Based on the information we have collected, the root cause of your disruption was not within the control of the airline or is due to safety-related reasons and therefore regulations do not call for compensation in this case.

As a gesture of goodwill, we would like to offer you an eCoupon valued at $300.00 CAD for you to use on your next booking on aircanada.com. You will find more detail about the eCoupon and how to redeem it below.

Please note that situations surrounding flight disruptions can be complex and have multiple causes. We are required to inform you of the reason for a flight disruption at departure but reasons may change as the situation evolves, new issues arise, or new information is received. We have made best efforts to identify the root cause of your arrival delay at final destination based on the information available to us in the time allotted under regulations. If you would like us to take another look, please let us know.