I bought both my Blackwings from Disbrowe in St. Thomas.
Small dealership, small town, but no waiting list for the first one and I was high enough the second time around that I even passed on an allocation for a 23 before pulling the trigger on my current 24.
Phone them and other dealers, big and small, and get yourself in line at any that have received one before, or other “specialty “ GMs like Corvettes or Escalade Vs, and who have a short (or no) waiting list.
I ended up turning down two Blackwings from City in Toronto using this strategy as my allocations there came up soon after each of the St. Thomas ones came through.
Paid MSRP for both my BWs and I wouldn’t be surprised if you could do better now.
Final bit of advice is not to worry about getting your deposit back if you put one in at more than one dealership.
I’m not sure if it’s an Ontario rule or law, but unless the dealership has a shady reputation, rest assured you’ll get it back if they don’t sell you a car.
Here’s a couple of shots of my two BWs on trade-in day (actually even made a small profit on the first, btw):