I’m curious what techniques the community has used to manage user > account associations, when users could belong to multiple Accounts but no way to ‘ungroup’. This is relevant for a lot of scenarios, but especially in the case of using Account-based audiences for Journeys and email. 

For example, let’s say John Doe - john.doe@gmail.com - is associated with ‘Blue Inc.’ via group(). John leaves Blue Inc. and joins ‘Red Inc’, and we capture that with group() some time later either via form fill or our offline data. Now John is associated with two companies in Segment, but only ‘active’ at Red Inc. We ‘know’ John isn’t at Blue Inc. anymore, but cannot remove the association.

We create an Account-based audience that Blue Inc. falls into, but Red does not, and want to push the list of all associated users to Marketo for email. John Doe falls into this audience because he’s still associated to Blue Inc. in Segment, so he gets an email when we wouldn’t have wanted that. I don’t think it’s as simple as adding another exclusion as that would remove users that should now fall into the audience (the reverse scenario).