Cedar Creek down on Lake Erie in Essex is the same day. I am sure that one will be more productive!
The following day is always Rondeau/Blenheim. My area includes Rondeau Park. The sloughs can be interesting in some years, but other years hardly any birds. The lake will be important for waterfowl this year, as the Bay is completely frozen.
Point Pelee is December 20--one I have never done.
Wallaceburg is on December 27. It includes Walpole Island which always turns up some interesting birds. Will be get Bobwhite this year? It has been many years since that has happened. They are becoming extremely scarce. I did Walpole one year and was lucky enough to get a few Bobwhite. I used to hear them almost every day in the spring and summer since I worked at the marina across from the north end of the island. I think the last one I heard was in 2005!. We also came across a Saw-whet Owl which was interesting since there are virtually no coniferous trees on the island. The owl was roosting in the middle of a deciduous woodlot!
St. Clair NWA is usually around New Year's Day and is a good way to start off the year.
I have been doing CBC's since I first started serious birding in the 1980's. I was just learning what was significant for a CBC. I had a male towhee in the yard that December and did not know how good it was for that time of year. I missed it the day of the CBC, but it was there the day before and the day after!
I actually came up with some decent birds on my first CBC.