The due date of an invoice can be changed by changing the net term. This will change when the customer gets billed and when the status of the invoice changes from due to overdue.
To change net term on an account:
Go to settings->financial->billing preferences->change the default net term value to Net0->click save
Note: This will only affect New customers moving forward
To change the net term on the customer level:
Go to customer dashboard-> settings (payment option block)
Change the term value and click save
To change the net term on the invoice level:
Click on the details of the invoice in question and change the terms on the invoice. This can be done for invoices in projected, draft and current.