It seems like the airport will not open as planned;
https://www.businesstraveller.com/bu...by-two-months/
Istanbul’s new airport was expected to open before the end of this month.
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Although there will be an inauguration ceremony to coincide with Turkey’s National Day on October 29 it is reported flight operations will not commence until the end of this year or until the beginning of January.
Germany’s Handelsblatt says that the government will be compensating the various airport businesses for the loss of revenue until the new facility eventually opens.