Here are the easy steps on how to change or set the wait list hold time.

From the Set up page select on "Wait List" where you can enable the wait list option:

This then allows you to see all available wait list settings including "Alert wait list party automatically when space becomes available for them":

This means that a notification will be sent to the customer as soon as there is an available spot and you can set the hold time for someone in the wait list as well (we do this in a first come first serve manner):

This setting also allows you to set a quiet time, where the system will not send any notification within the times you have set , for eg. 10pm-8am.

Select on the "Save" button to save any changes made.