By default, time selection option in reservation form has 24 hours options.
However if you want to customise this option to display only certain time period. For example your restaurant open-closed time. Please follow below instruction.
1. Open /js/custom-time.js in your theme folder. You will see below code.
jQuery('.pp_time').timePicker();
2. Let’s say you want to change select to 10.00 – 22.00. Please replace with below code
jQuery('.pp_time').timePicker({step:30, startTime:"10:00", endTime:"22:00", show24Hours: false});