I'm not who you replied to but I just googled the phantom time theory. The original claim is that it only spans 297 years(AD 614-911). I believe this is earlier than all of the genealogical records you're talking about.

I want to mention that I know nothing about this theory or these claims. I just learned about them in this thread so I am by no means knowledgeable on it.

Thank you I will check it out

I agree with a lot of what you said.

However I had to look up Doggerland because I hadn't heard of it. The first thing I thought of is that it looks exactly like the map of middle earth from lord of the rings. Do you know if Tolkien based the map on Doggerland?

I don't believe this means Tolkiens writings are real by any means but it seems like a very big coincidence that a fictional mythology of England looks exactly like Doggerland.