We are migrating from Office 365 Business to Office 365 Enterprise E3 licenses. Workstations currently has Office 365 Business version installed. Question is can user use Office 365 Business after license is changed to Office 365 E3? We are also reinstalling all Office clients to ProPlus version but it's hard to organize license change and Office installation happen at the same time.
It will still work, but in grace period. You do have to reinstall Office, as those two SKUs have different SKUs for Office as well, and those need to match between the installed version of Office and the license given to the user.
From my last experience, it was possible to change a business premium license to proplus or Enterprise without having to reinstall the office application. In the other way from proplus or enterprise to business a reinstall is the only way. I can imagine that the first scenario worked because the proplus is an "upgraded" version of business edition, like by windows servers it is possible to license a standard edition with datacenter key, the OS will be "upgraded" without issue but vice-versa it is not possible and a new installation is needed. Please let us know your progress Kind regards Spikar