How can we explain high redshift numbers?
There is evidence that this assumption is incorrect.


  Stars actually started forming before 500 million years post-Big Bang.


There is some evidence that Population III stars formed as early as 200 million years after the Big Bang. The oldest known star, the Methuselah Star, dates back to 200 million years after the Big Bang. It is a second generation star (judging from its metal content), so that means a generation of very large stars must have lived and died before this one was born.