After months of telling us that The Loft would eventually go back on satellite they made the move to on-line only permanent. Then they removed the DJ's except for the weekend specialty shows.
There's no such thing as a US signal or a Canadian signal, it's all the same signal from the same satellites. The only difference is whether you get the Sirius or the XM signal.
A receiver from 2006 may not be able to get Best of XM, it will tell you on your account page. If it is available, you will be able to upgrade instantly. If not, you will need to get a newer Sirius Receiver.