They mention the discount in this blog post: https://blog.agilebits.com/2018/03/28/the-1password-7-beta-f...

"Licenses will be available for $64.99 when we launch later this year, but are available now for only $39.99."

I just went through this - there's a tiny "downloads" link at the bottom of their page that takes you to https://1password.com/downloads/

I just went through this. Install v7, open it, unlock your vault, and it'll prompt you to try a subscription, with a tiny option below to just buy a license.