The packets are processed by a vendor. CO is notorious for mailing the packets out late. Check my earlier posting in this thread - I would expect them the week of March 7th.
From the picture on co.com under "my account" - it looks like the cards will have a new image. I would not panic. It is your onepass number in your account and on your reservation that counts.
Only issue many be international lounge access for Plats - but generally your boarding pass will show Elite status and it can be looked up.