We made a modification to the database that the listing available date is no longer required. If the listing available date is not entered, that listing will be always available, and it will show up regardless of your available date search criteria.
For example, a large apartment complex might not send listing updates often, yet always have certain types of apartments available. To make sure their listings always show up in your search results, you can set the listings available date to empty, this way, the listings will always show up in your searches regardless of what available dates you specify.
Avail. Date in Listing Details Page
To learn more about available date, follow the link below:
What is the available date field?