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To keep this tool simple, and so as not to confuse between potentially old vouchers and new ones, EVERY TIME you upload a new set, even to only a handful of parents, ALL voucher codes will be wiped from SCO, and the new set uploaded.
SCO SCO only stores one voucher per pupil and only that one is included on the mailings – all older ones are discarded permanently – so it is important to keep your own record with the original spreadsheet.
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