Here from Wikipedia is the explanation for the Dawn Upshaw concert:
Golijov came under scrutiny in 2011 for a series of high-profile commissions that were either delayed or cancelled. A violin concerto
written for the LA Phil was not completed in time,
and had to be replaced on the program. This followed a similar
cancellation in 2010, when a song cycle that was scheduled had to be
removed from the program when it was not complete in time. The March, 2011 premiere of a new string quartet for the St. Lawrence Quartet was also delayed due to a missed deadline.
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