16th and I expect a lot of fireworks on that day as exemplified on Apr expiry where SNDK up $4 to $22 now $26 and CREE down $3.5 to $20 now $20.75.
MM got to kill the potential profits of long call buyers while not rewarding PUT buyers. At least 2 transitions of UP and DOWN or DOWN then UP while removing time premium needed to shake out option buyers hopes and dreams.