Considering China's (ongoing!!) predicament caused by an oncoming, abject, demographic (urban, industrial) collapse, the obvious consequence is a stand-alone Japan's as the region's only remaining super power" ... Making this Short a no-brainer, probably well over a decade and a half.
The Long Term Price Target on this pair is: 10! (I.e. a >50% Decline ...,
... provided that there will be still such a thing as a convertible (off-shore) Yuan, further down the road - which, in itself, is very unlikely!)
[If you think Japan's debt levels are unsustainable, think again! China's >600% artificial credit expansion - in barely over a decade - is pure nonsense!!]