Timeslots allow you to control the flow of customers collecting their orders. Whether it[s for social distancing reasons or because you don't want to overwhelm your kitchen, you decide that you only want X amount of customers to arrive, every Y minutes.
You decide whether there's 5 minutes or 20 minutes between orders - it's totally flexible. You can also decide how many customers you can handle in each timeslot. Finally, you decide the minimum time you need between order and collection.
For example, you can have 1 customer every 5 minutes and the first ties lot should be at least 30 minutes away. Or you could operate 15 minute timeslots but allow 3 customers select each timeslot, and maybe you need 45 minutes between the order and collection.
To find out more about setting up your timeslots, check out this article.
Note that while it's highly unusual, it can happen that you receive more orders for the timeslot than you had intended. You can find out more about that here.