Episode 6x05, Fire and Brimstone, has been announced on CBS express:

http://www.cbspressexpress.com/cbs-entertainment/releases/view?id=37009

"Jane attempts to gather the remaining Red John suspects in one place". Brett Partridge and Bob Kirkland are not on the list of guest stars, so I guess it's true what many of you assumed already: Bob Kirkland will be ruled out as an RJ suspect in the next episode (6x04).