Once you begin an Exchange transaction, you can add the Exchange Fee Product to your basket on the Products step of the Box Office flow:
1. On the Order page, click Exchange
2. Select which Channel you'd like to exchange through
3. On the basket page, click the Event title to be taken to the calendar
4. Select the new Performance and Tickets you'd like to exchange to and click Continue
5. On the Products page, add the Exchange Fee Product which has now appeared for your Exchange basket
6. Click Continue to check basket before completing payment/transaction