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If the custom parameter is not set or if its value is neither SEPA_08 nor SEPA_02, the file generated will be in the pain.008.001.02 format (old SEPA version).
Supplementary data [OPTIONAL]
In this new version, your bank can publish data to be added to the bank files called supplementray data. This is optional for the bank, but mandatory for you to comply if the bank decides to publish some supplementary data. Please see with your banking institution for this supplementary data.
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