Hi,

All the registered versions support from Delphi 7 to Delphi 10.4, so with 1 license you can use both versions.
The licenses are perpetual, which means that they don't expire. When you purchase a license you get 1 year of updates, after this year, you can renew with a discount to get 1 year more or don't renew and you still can use the software but you won't get more updates or new versions.
There are 3 sgcWebSockets Editions: Standard, Professional and Enterprise. You can check the feature matrix here:

https://www.esegece.com/websockets/features/feature-matrix-delphi-cbuilder

Then you can purchase With Source Code or Without Source code. If you purchase with source code you can select to purchase 1 license, 2 licenses or a site license. The Basic edition (Without source code) only allows you to purchase 1 license. You can read more about FAQ:

https://www.esegece.com/websockets/faq

Kind regards,
Sergio