Adding exception date to EXDATES

Is there some easy way to add a single exception date to a TPLannerItem? The manual doesn't go into a lot of detail on this. Right now it looks like I have to write a routine using TRecurrencyHandler to do this. 

It is a matter of building the recurrency specifier.

You can use the class TRecurrencyHandler to build such recurrency specifier string.
In this class, you have the collection property ExDates where you can add an exception date. When you call the function TRecurrencyHandler.Compose: string, it will then generate this recurrency specifier string with the correct syntax for exception dates.