The evil NASA did not post images from 03Feb 20:40UT until 04Feb 05:09UT trying to hide the appearance of Mercury and confuse the easily confused.
-- Or maybe they were doing a momentum dump and safed the spacecraft for the burn?
Hiding data or normal spacecraft ops? You decide.

In any event here's the 1st image of Mercury appearing in STEREO Behind COR2 on 04Feb @ 05:09UT.
It's pretty obvious that it appeared earlier as predicted above:

[link to stereo-ssc.nascom.nasa.gov]

As a bonus, Mercury (seen here) will appear in the Behind COR1 FOV on 09Feb2010 at about 18:00UT +/-.

Have fun.


R.