In this case, if they're a resident of that province and a customer of that particular institution, then under this regime the federal rules would apply and they would approach that institution...and everything that follows suit. If they just had a general complaint about something, they could go to the federal regulator and lodge a complaint. There are many ways in which they could still register a complaint if they had an issue.
On November 28th, 2016. See this statement in context.