This is turning into such a sad saga, and unfortunately, as bad as this 4m sounds, this may not be the end of it. I also suspect that we won't even get that amount in the end.
Personally, I can't think of a more unfortunate situation. I mean, so many years have passed, and you would think that we (or Caldara himself) would hit a break, and turn things around, but it has kept getting worse and worse. It is also inevitable that he would manage a whopping ZERO Serie A appearance for Milan for his 40M price tag. Unbelievably shitty luck for every party involved.
aka xudong
Official: Loan with option to Spezia
He is Bosman next year, he will sign for free somewhere and another old flop chapter will close.
Actually he has a contract till 2024. Hence the loan with option.