FlyerTalk Evangelist
Join Date: Aug 2011
Location: Barcelona, London, on a plane
Programs: BA Silver, TK E+, AA PP, Hyatt Globalist, Marriott LT Plat, Hilton Diamond
Posts: 13,066
Presumably you mean BCN and not Qionghai.
Why don't you just call IB+ and cancel the unwanted flight leg? Pay the fee, get some Avios back and no worries...
In theory a recent court decision means that you could skip the BCN-MAD and be fine. In practice you might find your ticket cancelled if you no-show in BCN.