From Jim Wasserman's report in the Sac Bee, exactly as I predicted in this March post:
Some first-time buyers delayed scheduled April escrow closings until May to qualify.
"We had Realtors in the field say that was happening," said Appleton-Young (California Association of Realtors chief economist).
That might be a small, partial explanation for a fall in closed escrows from March to April, said Bob Bronswick, president and chief operating officer of Coldwell Banker Residential Brokerage in Sacramento and Lake Tahoe. He said some buyers managed to snag both the state credit and an $8,000 first-time federal credit that expired April 30.