Registration Form with Mulltiple Day and Time Possibilities

Registration Form with Mulltiple Day and Time Possibilities

I have two types of groups that can schedule on my form: those that can schedule morning or afternoon trips, and those that can schedule all day trips. My form currently works so that when a group wants to schedule a morning trip, only those morning dates that have not been "taken" or shown on my imported list. Once this date is selected, that date will now be "taken" and the appropriate record updated so that it is not shown to the next group scheduling.

My question is: how can I use an imported list to show only the dates that have both the morning and afternoon times available to groups scheduling all day trips? I am trying to set the import criteria to read, import only records that:
have both the morning and afternoon free, but only show the date once
and on update, mark the appropriate records with the chosen date as "taken"
I have shared my app with support
Please help, as I have tried many work arounds already.