You can create custom entry types to use in your Program Schedule View. This will allow you to keep track of all your non-Marketo agenda items that affect your program.
Go to the Admin section and click Tags.
Click Calendar Entry Type.
Click the New drop-down and select Entry Type.
Name your entry and select an icon.
Select an Entry Color.
Great! Now when you create a new entry in your schedule view, this type will be an option.
You can create up to 100 custom entry types.