It is my understanding from reading posts by Horizon reps on other forums, that the XL is on back order and will be available sometime later in August. Horizon is trying to resolve some of the deficiencies of the first batch before re-releasing. You did see the 2 service bulletins for the XL? They involve some re-gluing of some structural bracing. Some planes needed it, some didn't. They hope to ensure that all planes have been properly glued before release.
You may still find some product and parts at hobby shops around the country.