The New Delta Pre-Invoice Generation feature ensures that your invoicing process is accurate and up-to-date by comparing the latest invoiced amounts with new amounts and creating delta pre-invoice items for any differences. This feature handles various aspects of invoicing, including timesheet activities, flexible payment plans, packages, and invoice contacts, making your invoicing more efficient and reliable.
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The delta changes are made in the pre-invoice of their respective period or, if the period is closed for invoicing, the adjustments are made in the next open period. 
If a media campaign is running for more than 2 months and there are already invoiced invoices for the first 2 months and the invoicing period is closed, the delta pre-invoice will be created in the open period but the accounting date of the adjustment happening in the invoice items from first 2 period will be their respective date from the first 2 month.
How to call Delta Preinvoice generation
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