According to a statement from the Southern California festival, Knussen recently had surgery to "correct an abdominal problem." He expects to recover and return to conducting this summer.
Knussen was to have conducted two concerts at the festival, which runs June 9-12. Grant Gershon, music director of the Los Angeles Master Chorale, will replace him for a concert on June 11; Brad Lubman, a longtime associate of Knussen and a new-music veteran, will step in on June 12.
The programs remain unchanged, with music by Mauricio Kagel and Percy Grainger on June 11 and Knussen's Violin Concerto, a world premiere by Jonathan Cole, and works by Stravinsky, Lucas Foss, and Ravel on June 12. Peter Serkin is the piano soloist in the latter concert; William Preucil is the violinist.