Some thoughts: First, this should not cause problems with multiple deliveries since MM creates a set of recipient addresses for the message, which filters out duplicates. As for Member.__repr__() perhaps something like this (untested): def __repr__(self): if self._address is None: subscription = 'preferred={0}'.format(self._user.preferred_address) else: subscription = self._address return '<Member: {0} on {1} as {2}>'.format( subscription, self.mailing_list, self.role) Can you try that and see what you think? As for #1, I'm not sure it's a problem given the above, but if it does prove to be so, I can think of a few alternatives. Maybe the user should be disallowed from subscribing when an address they control is already subscribed with the same role. It's theoretically possible that an address could come under the control of the user after the fact, and that would be difficult to catch. Another possibility would be to convert the existing address-based subscription to a user-based subscription, but that might clobber the address that they actually want to get delivery on. E.g. they're subscribed with anne@example.com but their preferred is aperson@example.com. Any other ideas? I think if this is a problem, in the face of ambiguity, refuse to guess (i.e. disallow those double subscriptions). -- You received this bug notification because you are a member of Mailman Coders, which is subscribed to GNU Mailman. https://bugs.launchpad.net/bugs/837700 Title: Issues with users subscribed via their preferred address To manage notifications about this bug go to: https://bugs.launchpad.net/mailman/+bug/837700/+subscriptions