You can only extend your PGWP if you did not receive the full duration of your PGWP due to passport expiry. In other words, if you were entitled to a 3 year PGWP but only received 1 year due to the expiry date on your passport. If you meet these conditions, then you should submit an application by paper to extend your PGWP.
Just want to share my pgwp extension timeline.
Application may 5th
Was able to link it on May 29th
Approval November 16th valid till November 16 2021.
I was initially given 2 years and 6 months pgwp. To my surprise they gave me full one year extension. I hope it helps anyone who is in similar situation.
I did. On October 22 I received the approval (literally a miracle). Then, a week later, I got my permanent residence (LOL). I was playing safe but it turned out good! Good luck!