I'd say that they would keep a few for as long as they can. I think they REALLY don't want to deal with the thought of having to bring back the stored 201s which lets say the 071s are retired in 10 years, and none of the stored 201s had re entered service prior to that, the would have been in store for about 15 years and would need a serious rebuilding. Of course they could just buy some small locos, probably just 4 axle versions of the 201s, as Dave has mentioned above.