Error: "You've used a newer version of 1Password on this device." (See Approved Answer)

Here is what I got from support, it worked (I just had to enter the access data again):

I'm sorry to hear about the problem you've been experiencing with moving from the Beta to the Production version of 1Password 8.

To solve this, you'll need to move 1Password's Data folder out of the way so that it can make a new one. Here's what to do:

Right-click the 1Password icon in the menu bar (if it's there) and click Quit.
Open Finder, and click the Go menu > Go to Folder...
In the box that appears, copy and paste the following exactly:
~/Library/Group Containers/2BUA8C4S2C.com.1password/Library/Application Support/1Password/

and press Return.

You'll see a folder called Data - right-click on the folder and select Compress "Data".
Drag the original Data folder to the Trash.
Wait a few moments and then open 1Password 8. You'll be taken through the first setup process.