Though most JazzFest sit-ins remain a surprise until showtime, Ivan Neville has confirmed a handful of guests for Dumpstaphunks May 6 spot at New Orleans Tipitinias Upotwn. The Meters duo of George Porter Jr. and Leo Nocentelli will perform with the funk unit, which also features guitarist Ian Neville and bassist Tony Hall, among others. Porter will prove busy that evening also offering another set at Tipitinas with an expanded version of his Trio project with drummer Johnny Vidacovich. Throughout their set the duo will jam with an number of musicians, including Theresa Andersson, June Yamagishi, Trombone Shorty, Ivan Neville and Galactics Rich Vogel.