Hello, stobonet.
I'd be glad to help point you in the right direction regarding invoice due date via the QuickBooks Online.
So far, we haven't received similar issues reported. Since the Community is a peer-to-peer forum, I won't be able to check your account without asking for sensitive information.
All account related concerns need to be directed to our phone support for security purposes. You can get their updated number on this article: https://quickbooks.intuit.com/uk/contact/.
Also, these articles are a good reference:
Keep me posted if you have any other invoices related concerns, I'm more than willing to lend you a hand.
