Scheduled Messages

Currently, Ordering group doesn't suppport scheduled messages. Although technically possible, in practical use these two features shouldn't be used together. Because in some sense they are functionally conflict. Using scheduled delivery meaning you want each of such messages delivered at certain point of time in future, namely those messages must be delivered in the order determined by their scheduled times. On the other hand ordering group requires messages to be delivered in the order of sent sequence.

DLQ/ExpiryQueue

If a message of an ordering group is 'dead' or expired, it goes to the corresponding DLQ or ExpiryQueue and the message will be ACKed. Ordering Groups treat those messages are correctly delivered and completed when controling the ordering group delivery. Therefore, the consumers would see some message 'hole's during the receiving of ordering group messages. The 'hole's won't prevent their succeeding messages from delivering.