I created a new account and started the trial, then I chose the annual family plan. I was using the client from Agilebit Store, then I switched to the Mac App Store version because I prefer to pay with my App Store balance. However, on my Mac client, I can only see the button to subscribe monthly instead of annually.
My Mac client is the newest version.
1Password Version: Not Provided
Extension Version: Not Provided
OS Version: Not Provided
Sync Type: Not Provided