Originally Posted by
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You get the tags for the higher class to which you are entitled either by travel in that class or status. So a Gold who gets an op up at check in gets F tags.
Not true!
Based on numerous flights from HKG and ex-HKG, bags are tagged based on the fare class you purchased. So if you purchased Y, you will not get priority J tags nor lounge access, if upgraded to J at check-in. They usually will write "no lounge" on the boarding pass.