Queries can be configured to use the source timestamp in an event, by defining an action that returns the source time from the event's fields (performing any required transformation or parsing of the time). See Using source timestamps of events. Events can be marked with an annotation as not expected to arrive in order, and queries can specify an event type to use as a heartbeat to indicate that events have been delivered and are not delayed.

Queries can contain a with unique clause which discards all but the latest event when many events have the same value for a specified field. See Matching only the latest event for a given field.

When a number of correlators are operating in a cluster, failure of one of the correlators will now result in any timers which are active on that node being re-distributed to the other members of the cluster, so that timers are not lost. Note that Apama queries do not support reliable event delivery, so there may still be a small proportion of message loss as a result of a node failing.

The Pysys Apama extensions now support injecting queries as part of tests.