Company standard due dates on contacts
Contacts due dates to be set as a standard company wide setting unless changed within the individual contact.
For example as a company we work on the basis that all payments and receipts are due 30 days from invoice, this should be able to be entered within the company settings and should already be filled in when creating a new contact.
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This is essentially how the Default setting within the Invoice Settings work, Samantha. If you've set a default due date in this screen it'l apply to any invoices you create for all contacts, the only time it is overridden is if you have saved a default due date on an individual contact record, or manually change this within the individual invoice.