Canada FDC with two PMs

The Post Office FDC commemorating the Centenary of the Salvation Army in Canada is very common. The covers pictured here have extra PMs, and voilà; they are very seldom seen.  There is even one with TWO extra PMs. These are rare variants listed as SA 16.1b in the SA catalogue.

SA 16.1b - PO - w/ two extra PMs!!
SA 16.1b - PO - w/ extra Maple Leaf PM
SA 16.1b - PO - dbl PM - centennial logo