Is there an inhabited planet within 5 light-years of Earth?

From Future Of Mankind

Yes there is! It's called Akart and you can read about them in Contact Report 035. The Akartans have been coming here to gather food for quite a while already.

Their planet was massively overpopulated with over 23 billion humans which is probably how planet Earth will seem in a few centuries if we continue on our current path to "go forth and multiply".[1] Only 116 million were saved when their planet suffered an oxygen collapse.

Akart existed in the same space-time configuration as that in which the Plejaren live and did not exist in the space-time configuration of our Earth. The Akartans possessed time-barrier technology in order to enter our space-time configuration.[2]