I tell you what, when is your travel date? if its not within the next 1-2 weeks, let me go ask the transfer desk in the restricted area if they allow you to check in from there, then you can skip the immigration part.
One more thing you have to note if you are doing CX, smart casual no jean dress code. Not that they won't let you on but if Y is full, they may push you to PEY or C, and thats when your dress code comes into play. I got pushed back to Y once while holding a C boarding pass when they saw me wearing jeans. After that I never ever traveled wearing jeans or shorts LOL
Also odds are Y will be full and C will be quite empty, mostly will be maid and their families, no more summer holidays and public holiday. Except around 15 Sep there is a chinese holiday and another muslim holiday. actually come to think of it starting 15 sep (chinese moon cake festival) to like first 1-2 weeks of Oct (china national day), avoid CX and as they will use up all CX capacity. China long holidays are scary because you may run into days of no seats available. This is what happen when 1 billion people go on holiday
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