So its exactly once semantics, not exactly once delivery. Adding a dedup is not exactly once delivery, its being idempotent, its exactly once commit, we've had

So its exactly once semantics, not exactly once delivery. Adding a dedup is not exactly once delivery, its being idempotent, its exactly once commit, we've had this for years. Having clients request for committed messages and keep track of their progress is not exactly once delivery, its exactly once request. Exactly once delivery has messages pushed to clients. As blogs have noted this is not possible.