How to disable justification on expense items for spend authorization accounting difference?

Summary:

We are testing a configuration change in our system (not live yet). Previously we had the setting "Attach Authorization" set to "Header" but now we have changed it to "Lines"

This allows the user to apply their authorization to just one expense line, which we like. We are seeing that the user gets an error and justification is required when the accounting segments on the expense line do not match the spend authorization line. We do not want any justification to be required.

Our client's expenses will often be split across multiple accounts (which is only possible on the expense report - not on the spend authorization). This means that we expect a difference in the accounting segments on the spend authorization and the subsequent expense report. We do not want the employees to have to enter a justification for a difference in accounting segments. Is there a way to disable this behavior? I have not been able to find any documentation on this.