[rules-users] latest event within a timeframe

[Drools Version 5.5.0 Final] Hey - I got an event E1 that is only valid, if the latest event E2 following E1 within 2 minutes has the value 1 --> I want have the rule fire 2 minutes after E1 but only if E1 is valid This is my rule: rule "inform about E1" when //event (T1) is the initial trigger $event1 : Event(type == EventType.T1) //there is an event (T2) with value 0 between 0,2m after doorClosed $event2: Event(type == EventType.T2, value == 1, this after [0, 2m] $event1, $timestamp : timestamp) //there is no newer event (T2) within the timeframe not Measurement(type == EventType.T2, this after [0, 2m] $event1, timestamp > $timestamp) then //print info log(drools, "E1 valid"); end An example of Events: 12:00:00 - E1 12:01:00 - E2 ( value = 0 ) 12:01:10 - E2 ( value = 0 ) 12:01:40 - E2 ( value = 0 ) 12:01:50 - E2 ( value = 1 ) 12:02:10 - E2 ( value = 0 ) I would expect the output: [log() does log the clock-time when my rule fires) 12:02:00 E1 valid But what I get is: 12:03:50 E1 valid So I see that the late coming E2 (@12:02:10) is correctly ignored, the rule result is basically correct, but the rule is fired much to late. (actually 2 minutes after $event2 and not as expected 2 minutes after $event1). Could someone give me a hint what I did wrong? Regards, Alex