Aw, thank you! I :-* this forum, and will continue to stick with it until most of our group is through. It's good to see you back! I had been wondering about you.
I haven't had to do it, but from what I've read you just send a case-specific e-mail to the Buffalo office to let them know. You having an Ontario address should not be a problem. I was in Ontario for the whole process, and everything came through just fine.
There is (of course) variation, but my experience with the communications was like this:
Sponsorship approval: Mail
AOR: E-Mail
IA: Mail
PPR: E-Mail
Passport and COPR: Mail
What we've seen so far, most AOR's from Buffalo are coming by e-mail. And these are easy to get lost in your junk mail filter. If you get an Initial Assessment, it will probably come by paper mail, so that's what you'd be watching for next - especially since you're "In Process" now.
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But, as always, Buffalo is inconsistent, and anything Could happen. We've had a few applications sent off to satellite offices for processing, and I really don't know what the procedure will be like for those ones. The last PPR's from Buffalo were about a month ago. They've really ground to a halt.