More misleading evidence of Biden's electoral prowess

There's a poll out today in Michigan from MIRS/Mitchell Research that shows an uptick in Joe Biden's lead:

Biden +10?  Is it time to panic maybe?

Nope.  Back in 2016 the same pollster in the same window polled the following:

How did the state voting turn out? President Trump got 47.5% of the vote and Hillary Clinton got 47.3%. In other words they overstated Clinton's vote by 5.5% and understated president Trump's vote by 6.5%.  They were off by 12% total. And they had Clinton +12. If the same is the case in 2020, then we would expect to see the poll corrected to  Biden at 45.5% and Trump at 47.5%. That's a Trump win and improvement for Trump overall vs. his 2016 showing. 

When I look at valid polls in Michigan, and account for this bias (assuming it has not been corrected since 2016) I see Trump as high as +4.4% over three different valid polls.  While I do not believe it will be that high of a lead, I see him winning Michigan.