There are a number of different billers participating in this system where it is instantaneous. Under rule H6 of the Canadian Payments Association, the biller who participates will say yes, the day you pay is the day it's posted to your account. Absolutely. But not all billers in the country participate.
I can tell you that the Canadian Payments Association is planning to issue a document in the near future about the electronic bill system in Canada. They are looking for public input on it.