The replacement, presumed temporary until proven otherwise, is Kai from Esprit D'Air. There's a ton of full show videos on YT from the current European tour, feel free to check them out, he's pretty good, which is of course a total understatement.
However utterly bastard groovy Kai may be, it is indeed a shame about Dylan. The thread covering the first night at the Roundhouse in the Live section here on HL offers description of events, and of course more than a ton of wild speculation. His departure (aka sacking) is sad, but life goes on.