I think we have learned by now that these internal time frames are useless, but Phandroid has obtained a leaked document from a Sprint employee which states the HTC Hero has a “maintenance release tentatively scheduled for April 9th”.
The update will fix a bug with Sprint picture mail and we have no other details about what will be included. Sprint previously stated that an update to Android 2.1 was coming in early Q2 2010 which lead a bunch of sites to speculate April 9th is the day for 2.1, but I have a hard time believing that.
Hopefully in about two weeks we will get our answer. Until a United States carrier actually rolls out and update for Android 2.1 (to the mass public), I’m going to remain skeptical.