Routing Phase Out Date alert

Hello all, 

I am currently looking into a way to create an Event Action to notify a user via Streams that a Routing is approaching a Phase Out Date. 

I’m not quite sure how to do this, as there does not appear to be a way to trigger the the Event. 

The Phase Out Date would already have the date and it would not be updating, simply lapsing. In the screen shot below, Ideally a Streams notice could be triggered to send 7 days prior to 3/31/2021. 

Any guidance would be greatly appreciated!