If you want to regulate the rate at which you accept orders through your site for specified time slots, you can turn on Order Throttling. Obviously, this will only affect online order volume and not in-store volume, which is why you can turn the setting on and off whenever you need and do so for a specific location.
When setting up order throttling, you can choose to either limit orders in each time slot by dollar amount, number of orders, or both. If you set limits for both, a time slot will be considered "full" whenever the first parameter hits its limit. The time slots are decided by the Wait Time Ranges that are on the Order Settings page for each location.
Let's say you'd like to limit each time slot to accept up to $1000 in orders. Once you hit that limit, customers will not be able to place an order in that time slot and will be bumped to the next one. If a time slot has $750 already placed and someone places a $300 order, that time slot will still accept the order because at $750, it's not yet full. When it gets to $1050, it will then be considered full.
To set up order throttling:
Go to Locations and select the store you'd like to set up
Click on Order Settings and scroll down to Order Throttling Settings
Set your parameters and click on Update Order Settings