Canada Post is amazing. They have two addresses for customer service: one located in Winnipeg, Manitoba and one located in Fredericton, New Brunswick. For some inexplicable reason, eastern regions (QC, NB, NL, NS, PE) must use the Winnipeg address (central region) while central and western regions (ON, MB, SK, AB, etc) must use Fredericton (eastern region).
In other words a customer in Winnipeg must send a letter to Fredericton while a customer in Fredericton must send a letter to Winnipeg. Amazing efficiency.