Hi Everyone. I don't normally post here, but I thought that giving my timeline would probably help others that arrived around the same time I did. I was unable to link my account at all after landing, so I had no idea when the card would arrive or when it was mailed. Therefore, those of you who cannot link your accounts, please do not take this as a sign that your card is not being processed, because in my case I received my card although I could not link the account or track the process.
My timeline
Landed: February 27th, 2018 at Toronto Pearson International Airport
PR card despatched: Do not know, but assuming around April 17th/18th
PR card received: April 20th, 2018 (checked everyday for the past week, and finally yesterday afternoon, the card was in the mailbox)
I hope that this helps those of you who landed in Toronto around the same time I did and cannot link your account. I am thinking the card would have arrived a bit sooner, but the ice storm last weekend may have slowed the delivery process a bit.
I wish you all the best!