You do not need the animation wb for a first implementation because nothing is moving. You just need to use the python time module for the breaks, change transparency of the object and change visibility of the object in the regard of your new date property. The most cumbersome is to generate the input for this. Since every object needs a date. This could be a thousand or more dates. If such information could be imported it would be cool.
@Yorik and other developer:
Do we have a property which represents a time in words a date and or a time? Would be cool to have such property type for the stuff walpa would like to do. AFAIK we do not have such property type.