This is a continuation of a post from the beta forums, but since I can't get there anymore I'll continue asking it here. (cc @beth.lindner)
1) I had asked whether an iPad would receive the Lock command if it was locked but sleeping, since it normally will respond to other MDM commands with a NotNow (Busy). It turns out that it does indeed process the command correctly!
2) I don't see a way to unlock an iPad that I've Locked if it has been restarted, as it will not connect to WiFi networks until a passcode has been entered (I suspect an ethernet connection might work, but I don't have the 30 pin camera connection kit so can't try with my test devices). It seems a weird oversight for Apple to add it to the MDM framework this way.
3) According to Profile Manager documentation, there is also a way to enable or allow Activation Lock. On my test device that is locked, the iCloud Activation Lock web page doesn't show as locked, so I'm assuming this is something that has not yet been implemented? I also had to DFU restore the iPad from comment 2 above and did not have to bypass Activation Lock.
To answer my 2) above, I have created this FR, please vote up Send Clear Passcode to Mobile Device just before Enable Lost Mode command.
@beth.lindner Can you point a developer to my 3) above?