What the workflow after disagreement the band ?

No workflow nothing..they will conduct a formal meeting will say that rating is good n they will ask you to close the discussion

I received an email to discuss with my manager and reviewers and hr ask for the mom of the meeting. Let's see what will happen next

I don't think it has much impact even after disagreement. I have seen the manager might try to speak and then it will be closed.anyways, all the best . U would suggest do not keep high expectations.