Thanks for reaching out. You can use the apps in offline mode with a valid software license for a limited period. The apps attempt to validate your software license every 30 days. For more details refer to the below help article:
My internet has gone down today and it will not let me continue to use Illustrator. I am on a monthly payment plan for the full suite. A warning comes up and you cannot do anything - it just closes Illustrator down. Is there something I need to be able to do to carry on working? It is a joke if I cannot work offline, very bad service and affecting my deadlines with my customers.