... through the user's subscription tab in the back-end. I'm using CBSubs URL plugin, which includes triggers for deactivation and expiration. Neither of these appears to fire for deletion. Perhaps this is the expected behaviour, in which case a new trigger for subscription deletion is required. On the other hand, perhaps the likely required actions are the same for deletion as for expiration, in which case the expiration trigger ought to fire.
Julian
CBSubs 1.0.3, CB 1.2.3, J!1.5.20