Boston Symphony Orchestra Assistant Conductors Julian Kuerti and Shi-Yeon Sung will split the program on Saturday, October 3, which honors Ann Hobson Pilot's 40-year tenure as harpist with the BSO. Mr. Kuerti will conduct the first half of the program, Beethoven's Symphony No. 4. Ms. Sung will conduct Elliott Carter's "Mosaic," for harp and chamber ensemble, Debussy's "Danses sacrée et profane" for harp and orchestra, John Williams's "On Willows and Birches," for harp and orchestra, and Ravel's "La Valse," with Ann Hobson Pilot returning to the BSO principal harp chair for this special occasion.