From Labels select "Ingredients"
Then select which ingredient needs the calculated from "date on package" option, while hovering over the ingredient on the right-hand side three dots, and the option to Edit or Delete will appear. Click 'Edit'
From any phase you would like or in this example and HIGHLY RECOMMENDED USING the "Prepped" phase, you can then click the drop-down menu under Type and select 'Calculated date from package' then a new field will appear "Package Date Name", here you can type what you would like this date to be called if anything for example "Kill date".
Under expiration date you will then choose the total number of days that the ingredient is good for from the date on the package and remember to click 'Save' and you're all set.
When users print a label for an ingredient with a Calculated from date on package, they will be prompted to enter the date and then Zenput will automatically calculate the expiration date. Users will not be able to choose a date earlier than the calculated from date on package, i.e. they cannot choose a date more than 8 days in the past.