I think it's always been the plan for Charles to serve as king only briefly before passing the crown to William.
It's an easy segué from the longest reigning queen to her preferred grandson.
Charles doesn't have as much favor with the people as William, and is probably incompetent as he seems, from what I've seen, embarrasingly infantile and spoiled.
That said, Charles has already long been inexcusably affiliated with Jimmy Saville, so I don't think his name being in the flight log would mean a thing at this point.

Because of "Bloodlines," etc., it has been suggested that Price William is the Anti-Christ.

It's possible but not probable. I don't think he fits the prophecy for the Son of Perdition.

I've heard this suggestion as well and we also have to think bloodlines. An interesting theory for sure. In Daniel 9 and 11 and in Matthew 24 and in Mark 13 read about the Abomination of Desolation.
Here is a video from someone that threw the "antichrist" theory out there for discussion.
"This video is intended to be just a "teaser" to the very real possibility that Prince William is the Beast of Revelation."

https://www.youtube.com/watch?v=GT34cIASFqM&t=12s