How can we allow a user to add assignees to the requisition approval workflow?

Summary:

In "Configure Requisitioning Business Function", the option for "Reapproval required for changes made during an active approval process" was checked. An approver was able to add assignees to the approval process within the Manage Approvals page while that approver was editing the requisition (i.e. + icon available).

When we unchecked the "Reapproval required for changes made during an active approval process", the ability to add assignees while editing the requisition went away (i.e. + icon not available). Is there a way that we can keep the reapproval option unchecked but allow the approver to add assignees when editing the requisitioning during the active approval process?