The way I use Sendy is as follows:
When a user signs up, they get added to a list, say X. X has an autoresponder setup.
At a later date, based on user attributes, I create a new list Y that contains a subset of users from X to send an email to. For example, say Y is users whose checkout failed in May 2023.
When user unsubscribes to Y, I want to unsubscribe them from X and all other lists.
Is there a way to do this?