I got it and it expires Oct 31, same as OP.
I have no idea why I was targeted. I had done a ton of travel early in the summer and it all came to a screeching halt in July. Maybe that's why? I"m back on the road starting tonight and looking forward to those sweet, sweet loyalty points. Seriously though, I don't think the double points I get from this promotion are going to do anything for me. I'll make PPro again and that's it, just with a little extra breathing room this time. And I basically get upgraded on the same routes I got upgraded on as gold and platinum (that mainly being PHX-->ATL and back) so it's unlikely they will result in more frequent upgrades either.