First "As a thank you for being an early beta tester..."
After that "If you have any more than 20 UUID aliases they will be deactivated"
Should I go with you anymore? Never treat your customers as beta testers. My data come with UUID are gone.
A picture is worth a thousand words
The message stated: "You are currently on a Free Pro Subscription as a thank you for being a beta tester. This free subscription will come to an end on 5th December 2019. You can still start a subscription now if you wish to support AnonAddy."
When the site's open beta came to an end I sent an email to all those who had signed up. As a thank you, this email let all users know that they would have an additional 3 months to continue using all the Pro features of the site for free.
I then sent 2 more emails shortly before this free subscription came to an end which is shown in your screenshot, giving users the choice to update their emails if they didn't wish to subscribe.
I have also offered all beta users a discount on both Lite and Pro plans.
Let me know if you have any other questions.
Best, Will