B2B Ecommerce Integration for XERO to Set due date as 20th of month following Invoice Date

Apparently I am the only one who uses Big Commerce or other E commerce website platforms to sell to other businesses and am stuck with Onesaas's irrational method of only allowing an invoice due date to be set as the X days after the invoice/sale date.

This means once a month I have to log into Xero and manually update all the due dates on out standing invoices to the correct terms of trade due date of the 20th day of the following month.

Would you please add your support to have the integration also allow us all to set a specific day of the following month to have an invoice due.
E.g. an invoice/order received in January is due on the 20th day of Feb

This is very common business practice in New Zealand. I believe Australia may be similar.

Please Ask One Saas to escalate this to a higher priority
I have been asking over 2 years and am told I am the only request for this feature, so don't be silent Unite with me =)

Thanks