It is now possible to routinely perform atomistic simulations at the microsecond timescale. In the present work, we exploit this for a model binary Lennard-Jones glass to study structural relaxation at a timescale spanning up to 80 microseconds. It is found that at these longer time-scales, significant mobility and relaxation occurs, demonstrating a reproducible relaxation trajectory towards a class of asymptotic structural states which are strongly heterogeneous. These structures are discussed both in terms of the ideal glass state and a production route towards novel amorphous crystalline nano-composite micro-structures with strong interface stability.