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How to swap a session if the period has already been invoiced
If a parent wishes to swap a session in a period that has already been invoiced, and you don't wish for them to pay for an extra session, you can use the method below to effectively "swap" a session:
Set the child to be on holiday for the original, invoiced session.
This will remove the child from the register, but the session will still appear on the invoice
Add the new session as an ad hoc purchase on the right day in order to make the child show up in the register. Remember to add a full discount of the ad hoc session so the parents aren't charged twice. To add a discount, click the "..." in the top right corner, when adding the ad hoc purchase.
Note: Just make sure that the sessions you swap are priced the same, so the parents don't over or underpay.
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