The only ones that should be surprised are the children of darkness and they will see the return arrive as the 7 vials unfolding, the children of light will see that day arrive as detailed in Re.10. I'll wait till this post gets a reply before offering my comments on another part of the OP. (to keep them reasonably short)
You gave the answer yourself, there is still a reference to demons, having a multitude of resurrected people alive and chatting is the first sign that you have made it into the first day of the Kingdom of God being on earth. If you don't experience that you get to wait 1,000 years and then you meet God right away, that is the more fearful way to meet Him.