As a default option, the order goes automatically into production, one hour after it has been place.
If you wish your orders to not get automatically sent into production, please make sure your order settings are set to manual, thus, it will be processed as a manual order. For this case, you are allowed to chose your preferred hold-time.
The hold-time starts from the moment your order is placed and is allowing you to cancel it during any moment before it has passed. After the amount of time you chose (eg: 3 hours) has passed, your order will be sent into production and cancelation will no longer be possible.