As Climacograptus typicalis is the most common graptolite found at Bowmanville, and in my experience everywhere in the upper Ordovician, I should not be surprised to find it in the Collingswood member of the Whitby formation. I have only found one specimen so far and it is super hard to get a good photo of the black carbonaceous film on black shale. But in the second photo below you can see the square shape of the thecae where the animals lived.
The Whitby formation is Ordovician in age (late Ordovician, Katian/Mohawkian stage).
fossils were collected from the St. Mary's Limestone Quarry in
Bowmanville, Ontario. I used William Hessin's book "South Central
Ontario Fossils", 2009, Self Published, pg. 263 to help identify these