Is it possible to switch back to the new version of estimates and invoices. I accidentally switched to the old version. I need to collect deposits, but can't now.

It's good to see you here in the Community, natedove.

I know how important it is to have the option to switch between the old and new estimates and invoices, however, this is unavailable in QuickBooks Online.

While it's unavailable, I'd suggest submitting feedback within your QuickBooks Online (QBO) account. This way, it goes to our product developers to help improve your experience while using the program. Here's how. 

1. Go to the Gear icon at the upper right and select Feedback under Profile.
2. Enter your comments or product suggestions. You can also attach a screenshot or file to combine them all.
3. Click Next.
   
4. You'll be provided a list of suggested help articles related to your comments. You can read through them or choose Skip and send message.
5. Select the appropriate category from the drop-down menu.
6. Tap Send message.

In the meantime, you can take a look at the write-up to help guide you with utilizing your templates in QuickBooks Online as well as on what other information you can add: Customize invoices, estimates, and sales receipts in QuickBooks Online.

I'll be right here if you need further assistance, natedove. Just leave a reply below and I'll be around to help. Have a great rest of your day!

Is there no way that someone could help me revert back on the backend?

@natedove 

Consider open a new account.

https://quickbooks.grsm.io/US

https://quickbooks.grsm.io/us-promo

then utilize a 3rd party app to duplicate data as a workaround.

https://rewindio.grsm.io/copy

Just found out that you are unable to switch back.  Nowhere did it state this.  How upsetting to learn after the fact that you are unable to switch back to the new layout once you switch back into your old layout.  Very upset at Quickbooks for doing it this way and not warning anyone !!! Don't switch layouts!!!