Hey @Jricci11 , This can be achieved through a workflow. Here all the subscriptions will be updated and it is an automated process once you set it up at first. For Example, if you have a Subscription type Finance and Marketing, and you are sending an automated email to all the contacts whom you think would fall under the Subscription Marketing, then you can add an option titled “Add to Subscription” in the same workflow from where the automated emails have been sent.
Let me know if this helps.