If you'd like to set up specific date's online order item capacity, please refer to the following steps and modify on ipad :
Click Settings > Food Order Management > + Add
Enter the module's name, etc : Christmas > Select the date that you want to apply this module on below calendar > press Done
Tap on Order item capacity control of Christmas module
Tap on Unlimited under Total & Setting or the orange boxes on the right side.
In there you will be able to set up its provided period and capacity.
When finished, tap Done and then tap on the Done on the top right of the page.
