Date Picker change trigger

I have a trigger that changes one element’s time based on changes of another element time (done by a date picker).

The date picker is on auto binding and I expect that changes should always follow to the second item, but…
When the user just changes the time or just the date - the trigger is not launched. So it is required to change both in order to make this work.
Anybody solved this issue - is there a trigger that updates the element even if just one of the elements has changed?

Hey I was just testing this, using the default date/time picker as a trigger

It was triggering any time i changed the date OR the time, what does your setup look like?