What I did (last year) was to make sure they had at least read https://www.microsoft.com/en-us/WindowsForBusiness/End-of-IE-support https://www.microsoft.com/en

What I did (last year) was to make sure they had at least read https://www.microsoft.com/en-us/WindowsForBusiness/End-of-IE-support https://www.microsoft.com/en-us/WindowsForBusiness/End-of-IE.... IT only pushes back because the business users who use old web apps push back. Gotta make sure that IT knows the MSFT no longer has their back and so they need to be more aggressive with the business users and their app vendors.