How would Beijing respond to yuan revaluation?

Most of all the Chinese leadership is worried about maintaining jobs (sound familiar?).  And so:

It will lower real interest rates and force credit expansion 

This of course will have the effect of unwinding the impact of the renminbi appreciation.  As some Chinese manufacturers (in the tradable goods sector) lose competitiveness because of the rising renminbi, others (in the capital intensive sector) will regain it because of even lower financing costs.  Jobs lost in one sector will be balanced with jobs gained in the other.

But there will be a hidden cost to this strategy – perhaps a huge one.  The revaluing renminbi will shift income from exporters to households, as it should, but cheaper financing costs will shift income from households (who provide most of the country’s net savings) to the large companies that have access to bank credit.  So China won’t really rebalance, because this requires a real and permanent increase in the household share of GDP.  Instead what will happen is that it will reduce Chinese overdependence on exports and increase China’s even greater overdependence on investment.

This will not benefit China.  It will fuel even more real estate, manufacturing and infrastructure overcapacity without having rebalanced consumption.  Expect, for example, even more ships, steel, and chemicals in a world that really does not want any more.

That's from Michael Pettis, and here is more.