Finally got shipping notification of my order (as of yesterday evening, it was still pending and without a shipping # on SAE's website). This was a big order placed within 3 minutes of going live on March 19, though not fast enough to get the signed copy.
Every time I've ordered in the last couple months I'm one of the last ones to get a shipping notification. As far as I have been able to deduce from everyone's messages, these things that apparently count against me: 1) buying more, 2) buying as soon as preorders go up, 3) living only a few states away. Makes complete sense.