No replacement date was announced, and although a story by Calvin Wilson on STLtoday.com refers to the event as "indefinitely postponed," an email from a representative of promoters Sky Promotions used the word "canceled," suggesting that none will be forthcoming.
The email also stated that "the processing of refunds on Eventbrite is underway," but the Eventbrite page for the concert still had no mention of any cancellation, postponement or refund procedure as of 12:15 p.m. Thursday. However, the show has been removed from the Chesterfield Amphitheater site, and the URL ecomusicfestivals.org that originally was used to promote the event is now redirecting to the EventBrite page.
Wilson's story says that the promoters are citing the current unrest in Ferguson as the reason for the cancellation; the story also drily notes that the Chesterfield Amphitheater is located more than 20 miles away from Ferguson.
Given that promoters were still soliciting vendors for the event via Twitter as recently as this past Tuesday, August 19 - 11 days after people took to the streets to protest the shooting of 18-year-old Mike Brown by a Ferguson police officer - and tensions on the ground there seem to have eased somewhat since then, one can't help but wonder what's happened in the last two days to prompt the cancellation now. Perhaps a report indicating poor advance ticket sales?