It'll look like a new machine to ePO as it will have a new GUID I believe.
To pre-populate them into ePO (in 4.6.6 anyway), you can do that in System tree> New Systems (bottom left of screen)> Import systems from a text file (group name) but do not push agents. But that'll require some interlock from the folks building the systems.
What the environment I'm most familiar with does is check the lost and found daily and move them where they need to be.
I believe there's something with AD that can also be done, but I'd defer to someone who's done that to say more.