If these lines need to hop off onto their network there is no way to hide it as they need to bill you for it.
I think they will be less likely to scrutinize what you are doing if you have business type circuits terminating in an office building. i.e. E&M or t1/e1 circuits.
T1 is a carrier that allows 24 voice calls or 1.544 MB of data to be carried through it.
Redundancy is generally used for data circuits when one fails the other can pick up the rest of the load.