You've mentioned V6 & 360 - by means of advice, whilst the boxes are the same hardware, in all other ways they are completely different platforms. I'm presuming then, that you've asked to migrate to 360 whilst also ordering a multiroom setup.
You're quite correct re the additional install being on-hold, and for as long as there's no coax point in the room you want the second box, that's not going to happen. I suspect it may depend which order was put through first, or whether VM's systems will even allow multiple orders.
There shouldn't be any issue with ordering a single-box migration from V6 > 360, but I have a horrid feeling the addition of multiroom into the equation may have complicated things.
This is one case where I think you're best waiting (a day or so) for the forum staff to pick this post up and advise where to go from here.
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