Setting criteria with Created time without specifying date - presales question

Setting criteria with Created time without specifying date - presales question

I'm trying to set an SLA criteria to apply different business hours based on when the request is created.

I tried putting 'Created Time' 'is after' '<blank date>' '6 00 PM' on the SLA Execution Criteria section, but I can't save it because the form requires the date. 

Can support please help thanks!
Martha