Hello, I am in the exact same situation as you. I am a Canadian PR, and I was looking to get my initial H1B stamped in Canada, but I currently live in the US. Since there is very limited appointments available at this point, I was hoping to "send documents" from Canada since we can travel to Canada anytime as a PR. My understanding is, as long as I am in Canada with legal status (i.e., PR) then I can waive the interview (based the extended interview waiver). Could you please share if you have heard back from customer support regarding this matter? Many thanks!