This answer is largely the same for all types of users, but, in an effort to be thorough:

• Pre-existing users (if you bought SGPro pre-subscription):  Without a subscription you will be able to use the latest version of SGPro 2 or 3 (depending on which you purchased) indefinitely, but will not be able to upgrade as new versions of SGPro are released.  In addition, you will not be permitted use of the “Premium Support” forum, but will still be permitted to use the public forum.  In order to continue use of SGPro, you will be required to use the new SGPro licensing system in order to continue using SGPro.  Your new account and licensing have already been created and are waiting for you to claim them.  Please check your Inbox (spam folder too) and locate an email with subject “SGPro – [IMPORTANT] Your New Account Information”.
• New users (if your initial purchase of SGPro included an annual subscription):  Without a subscription you will be able to use the latest version of SGPro available at the time your subscription expires.  You may use this version (or any lower) indefinitely, but will not be permitted to upgrade as new versions of SGPro are released.  In addition, you will no longer have access to the “Premium Support” forum, but will still be permitted to use the public forum.