Wow, that's good you called - although I really don't agree with what the Call Centre agent told you. The VR will be valid until the date it's set to expire. It should be issued valid for however long they give you (6 months, a year, whatever), or until your passport expires, whichever comes first. So, the fact that they issued the VR valid until August 2011 with your old passport number (that would have expired in Sept 2010) is just another indication that someone simply forgot to change the passport number in the computer before they spit out the VR - but the Call Centre agent is NEVER going to admit to anyone that someone at CIC screwed up.
So, I seriously doubt that your temporary status would have actually expired when your "old" passport did . . . how could it when your "old" passport doesn't even exist. It's been replaced, with a new passport with a new expiration date, and you have a new VR with a new expiration date also. Still, it's good they're issuing a new document to fix their error - just so it doesn't cause any confusion. They should give you an extra couple of months for your trouble - but don't hold your breath.
And so glad I called..I was calling to make a complaint about my Visitors record! It is a re-extension and my maiden name and old passport number were on my previous one..I re-newed my passport back in October 2009 as I got married then submitted a copy of my new Passport in my married name when I applied to re-extend my VR...
So glad I called!! I could have been out of status without knowing...Although it would have been CIC`s mistake...So a new document is being issued and should get here within 10 business days!