I think, This feature request does not make much sense because what Commerce_...

I think, This feature request does not make much sense because what Commerce_Reorder does is "creates new order" in "Shopping Cart" state.

Where as the billing information / Address-book details e.t.c are entered by user @ Checkout page, And the order there is in "Checkout" state.

Hence your request seems to be against the basic objective of this module.