On End Date Send a mail to Sales person

Hi 

In custom entity I have start date and end date,

When end date is = Day after end date then I need to send a mail to Sales person that record date has expired

I have Written workflow for this below

Wait Condition
Custom entity End Date = End Date and
Process Execution Time = 1 Day After End Date then
Send Mail to Sales Person

But I'm bit confused about the on which event I need to trigger this logic.

Thanks,