Your Canadian PPL should be valid without any formalities, certainly for day VFR, maybe for night flight as well depending on whether or not it technically permits IFR. See:
<A HREF="http://www.srg.caa.co.uk/pld/fcl/fcl_faq_detail.asp?ID=178" TARGET="_blank">http://www.srg.caa.co.uk/pld/fcl/fcl_faq_detail.asp?ID=178</A>
|