Skipping First Flight?

Looking for anyone's experience with requesting cancelling our first flight through Air Canada. We have a trip to Japan coming up in April and are planned to fly from Airport A to Airport B with a 2.5 hour layover and then to Japan. We opted for this choice because it was cheaper than just going from Airport B to Japan.

The issue is, they now have pushed back our Flight A twice and we will now only have an hour and fifteen minute layover. In a perfect world, we would be able to make our second flight. The issue is, there is a high possibility that our flight won't leave exactly on time and I am nervous we will miss our connecting flight. We live about 2 hours from Airport A and 3 hours from Airport B, so driving an extra hour to Airport B is not that big of an issue. All flights are operated by Air Canada.

Has anyone ever reached out to Air Canada to make a request to skipping their initial flight and flying directly from their connecting flight?

TIA