The plays of Brett Neveu are frequently suffused with inopportune moments, so perhaps it's fitting that 16th Street Theater's remount of "The Last Barbecue" experienced an untimely shift of its own when lead actor Matthew Brumlow was hospitalized with pancreatic inflammation less than 24 hours before the show's opening. With a subscriber base and a marketing push already under way, the show must go on -- even if that means pushing back opening night by a few days.