Yes, the event model is the only thing that makes sense. Just wanted to say, I don't think Kent's idea is in conflict with the Event Sourcing pattern, as long a

Yes, the event model is the only thing that makes sense. Just wanted to say, I don't think Kent's idea is in conflict with the Event Sourcing pattern, as long as these "Effective/Posting" events are stored append-only. Once you start updating the "Effective" date, you're losing data (a customer might call back and ask what the old Effective date was, to understand a paper bill, and you've lost it).