This means that there isn't a limited number of exam appointment dates. Available exam appointment times will be available to view and schedule after your application has been approved. Most exam centers offer exam appointments Monday through Friday, with some offering Saturday appointments, as well.
Once your application is submitted and approved you will be provided a 90-day authorization period to schedule an exam appointment and take the PTCE.
Pearson VUE test center locations offering the PTCE can be found here.