It's not a weird email. When you get an offer you two different emails. One from the contractor that invites people to the pepc(the one that people received thur and fri), and a second one from your HR person with forms attached to send back to them(the ones from today). It seems that there has been no PEPC emails at all today and that some of the HR people are ahead of those emails. The same thing happened for the PUBNAT 2 emails. They didn;t change the format, every person with an offer is supposed to receive both.
Thank you for the clarification on this. It's getting a little confusing, but it seems like the ball is rolling. I hope the contractor gets their act together and sheds some light on this situation.