"New" Invoices going to "Old" invoices with a link to switch to New, but it goes back to Old... What is going on?

I recognize the inconvenience this caused you and how this unexpected issue has interrupted your business, @bvstone. 

As of now, QuickBooks Online is in the process of introducing a new invoice experience. Thus, QBO will continue to roll out this update and gradually apply it to all users. 

In the meantime, you can do this workaround to fix this issue that you have experienced. By doing these basic troubleshooting steps, we can identify if this is a browser-caused issue. To do so, we can use these keyboard shortcuts to go to incognito or private mode in your browser: 

• Google Chrome: Ctrl + Shift + N
• Mozilla Firefox: Ctrl + Shift + P
• Microsoft Edge: Ctrl + Shift + P
• Safari: Command + Shift + N

We can also clear our browser's cache so the system can restart and operate with an updated supported browser to run QBO properly.

If the issue persists after performing the troubleshooting steps, I highly recommend contacting our support. They have the right tools that can help with this issue.

1. Go to the Help icon.
2. Click the Search tab and select Contact Us.
3. Provide a summary of your concern, and click Continue.
4. You can either choose Chat with us or Have us call you.

You can contact us from Mondays to Fridays, 6 AM to 6 PM PT, and Saturday, 6 AM to 3 PM PT.

If you want to personalize the appearance or layout of your sales forms, you can read and review this article: Customize invoices, estimates, and sales receipts in QuickBooks Online.

Keep me posted if you have any questions regarding invoices in QBO. The Community forum will always be ready to assist you.