My husband asked Scott if they had a new bass player yet and he said that
they would not be replacing Brian at all. He said that he and Mark would
play the bass tracks for the recording and that they would hire a tour bass
player for the road.
Scott said that they did audition some people but decided against it because
the three of them were so close, and they were afraid a new person would
throw off the chemistry.
So, for the time being anyway, one mystery is solved.