Sent a Twitter DM to Aeroplan asking about the kits not arriving and noting that plenty of others are in the same boat. Got this response:

“Hi, you are correct, there was an issue with the delivery of Elite kits. This should be resolved shortly, and kits will be sent out mid-May. In the meantime, you can download the Air Canada app on your smart phone to have access to the virtual card. We apologize for the inconvenience and appreciate your patience”

So, the current story is: maybe another six weeks!