In favor of a home-grown OS I assume?
Pretty much, the concept of COS (Chinese OS...dumb name) is to develop a China-exclusive OS for government and military agencies, so there's no need to worry about NSA backdoors or MS dropping support (ex: XP, which is still being used by most government agencies.)
Anyway, there are many rumors as to why this delay roller coaster is happening, but changing the OS is definitely not one of them (Since we know that some consoles are already in retailer hands. Something as serious as an OS change/opposition would have made them recall all those units.)