I do not think you understand. Please allow me to clarify

Users would not be using different versions of QuickBooks for the same file

Users need to use different versions of QuickBooks for DIFFERENT files.

We have hundreds of quickbooks files for clients in many different years and versions

For example: CPA firm has three clients

Company A uses QuickBooks 2021; we need to use it in multi user mode.

Company B uses QuickBooks 2022; we need to use it in multi use mode.

Company C uses QuickBooks Enterprise 20.0; we need to use it in multi user mode.

Once we properly install QB 2022 for multi user application, the multiuser mode is no longer allowed in QB 2021 or earlier versions.

Is there a fix for this?