What is CCTB? The only thing I am aware of is that you become a PR on the day that you land. If you had a work permit or another visa than the PR visa, they will probably invalidate it when you land. There is nothing you have to return when you leave as far as I know.
CCTB is "Canada Child Tax Benefit (CCTB)" govt pays some amt to you for your child below 18, so will this start for above condition from 1st day? Any current CCTB receivers can throw some more light please...Sorry Leon for not explaining earlier..
I don't really know about child tax benefit but I would assume it starts when you take up residency in Canada, not when you land. You can be a PR of Canada and live somewhere else in which case, why should they pay you benefits?