How to prioritize Absence over Time entry automatically

Summary:

If the users have existing time entries on the day and schedule full day absence for same day, this absence should have higher priority over existing time entries. Otherwise the user needs to delete all time entries. 

Content (required):

We are using Time and Labor which is integrated with Absence module. So the absence appears on time card together with time entries.

If the user have existing time entries on some day and schedule full day absence for the same day, this absence should have higher priority over existing time entries. Otherwise the user needs to delete all time entries.