Not sure if others gave you all the info you need but as someone said - unless you can make a case (supported by serious evidence, ie. no longer have a Cdn driving license, have no immediate family, etc) for not having residency ties, the Canadian govt will come looking for the difference in the taxation of what you would pay in Canada (which is a higher % than in the
UK on teh same Cdn$) and what you are paying the UK govt. Definitely a drag but I understand from my tax accountant in Canada that you generally would need to be out of Canada a min of 2 years, possibly longer, before they'd accept the case that you don't have permanent ties. Having a house or other things back there makes it more complex.
Good luck.