Given a travel related situation, and given a specific question about the situation, summarize the question into a title

Q: If I stamped my passport for an international flight as we usually do before international departures and then I changed my mind for any reason, for example a family emergency reason. What's the process to cancel the stamp and leave the departure area?

A: After passing through immigration at the airport, is it possible to cancel the stamp and go back?
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Q: While searching the fare spectrum for London - Birmingham, I found these but the main BRFares listing(at the bottom of the page) says "Not normally available for purchase." When are these tickets available and how does one buy them?

A: Very cheap but inaccessible UK train fares
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Q: I recently got an APEC card, with validity for countries like Indonesia & China, which normally have higher visa-requirements for me as a UK passport holder than other countries (no visa-on-arrival, full-page stickers in my passport etc).

The APEC card is supposed to give me Visa-free access to those countries, but I am worried of traveling and then being bounced back at passport control. Can someone tell me from their own experience if they had any problems trying to cross the border with an APEC card despite normally requiring a visa to China?

A:
Does an APEC card reliably grant visa-free entry?
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