We may still be hours away from the start of So You Think You Can Dance‘s Top 20 competition, but there’s already been a change in the lineup.

Despite postponing Juilliard to appear on the show (and making Adam Shankman cry during the audition phase), contemporary dancer Billy Bell will be off the program altogether. Although the 19-year-old was seen during last night’s pre-taped showcase, an illness has forced him to end his run. He will be replaced tonight by 21-year-old Brandon Dumlao, a hip-hop dancer from California.

According to statement from Bell’s family, continuing with the competition could have meant grave consequences. “We were all very disappointed when we heard the news and Billy was devastated when his doctors told the show that if he continued to dance on the show before he recovered, he could possibly die,” it read. While a specific diagnosis was not mentioned, Us Weekly reports Billy is being treated for mononucleosis.