Have you contacted Aviva Elite directly (Wayfarer's underwriter) and asked for their take on your situation? They'll likely just point you to a different broker who can't answer your question... but after that fails, you'll have cause to contact Aviva's Ombudsman who will be able to unearth your answer for you.
In the end, I suspect that they'll tell you that the vehicle must return within six months (and almost certainly, if its financed, the finance company will stipulate some conditions), and I have a slight suspicion that there is a requirement in Ontario's Insurance Act (or some related legislation/regulations) that the vehicle be in Ontario six months a year. Aviva's Ombudsman will be able to dig that up for you.
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Of course, you may be able to register and insure your motorhome in another jurisdiction, but then there is a whole host of residency requirements that will have to be met. You may find some leniency in the territories or Newfoundland, where residents are more typically out-of-province for long periods of time.
