Check the dates of all rehearsals that will be required for all actors. Usually this will be your tech week but you may choose to include other rehearsal dates as well.

This explanation will appear in your form. In the conflicts calendar, any rehearsals you designate, plus the performance dates, will be marked as required dates. Required rehearsals usually include tech week, but may include other dates, and you can explain that here. Also you may want to give full details on the performance dates and times.