We have received many-many requests from CS-Cart store owners to add the ability to select the availability on hour level. In this version we have implemented this feature. Now have the ability to set up the availability to minimum one hour.
We have fixed a small bug, mass product editing deleted the availability periods.
Also there are some other code optimizations to improve the speed, stability and security. Update is highly recommended.
You can download the latest version from your account. Un-install the previous version and install the latest one.
More info: Product Availability Manager v4