This story was leaked to the Washington Post by the Mueller people. There is no way to verify what really happened or why Strzok was really reassigned.
Page left in June. Strzok was reassigned in August.
Why are they only reporting it now?
When did Mueller and the Washington Post ever have a problem with someone being pro Clinton or a person being critical of Trump?
I doubt the story is accurate. Just more disinformation from Mueller and the media.
“The Russians” taught the FBI what dezinformatsiya is.