Once a travel request has been approved it cannot be modified; however, some changes can be reflected in the header for the expense report for the trip. The start and end date can be changed if the trip is changed by only a few days. The fund allocation can be modified. However, the Trip Type and Trip Business Purpose cannot be changed. If these fields change or the trip is extended or changed by more than a couple of days, a new request must be created and approved. Any changes to these fields should be explained in the trip header comments.