All four heritage units have now been released, with the final two going over to Washington D.C. on the Capitol Limited yesterday. Here they are during a quick station stop in Cleveland:
Amtrak 184 and 66
Right now it seems all 4 are in or based out of D.C. I would assume this could be to keep them all close until National Train Day so they are all ready.
Also, for the Museum train, according to this schedule it seems like it will only be on the east coast, or have they just not released the full thing?
Amtrak Ink