There isn't a specific language string for that checkbox. Do not allow people to have access to those pages if they do not understand how to properly utilize them. Management access should be heavily restricted. A confirmation dialog warns you it is about to completely wipe the subscription from the database. You should be able to extend that message further using language overrides.
Have added a feature ticket to improve the delete behavior to check for recurring subscriptions and either cancel them or block the delete.
forge.joomlapolis.com/issues/8338