ATSU Address Unknown

[SirXape]

Hello,

This is my first post ever.

I have been decoding ADS-C messages lately like the following: /REKCAYA.ADS.JA882J14349E9F8E428985AA999F0D2E38E7C7 1C898590F12B60B7D21C098580FFD9.
These messages are sent to different facilities and contain the ATSU adress, for example this one is sent to Reykjavík (REKCAYA), but there are many more, PIKCPYA (Shanwick), JEDAAYA (Jeddah) and so on.
But I have encountered some that I'm not capable of knowing where they are located, for example QUKAXBA or HDQBQSK or SKYSWSQ. If anyone has an idea where these locations are, I would be really grateful. I'm located in Zurich in Switzerland, if it can be of help.

Thank you so much in advance

[RonBlue]

These are IATA communication network addresses which are 7 composed of 7 alphanumeric characters (usually all alpha). The last 2 letters are the airline code (e.g. BA British Airways) or agency code, the first three letters are the location designator - usually an airport code like PIK or JED but sometimes special locations assigned by the airline like HDQ (headquarters). The middle 2 letters are the "office function designator" which have some IATA standardization but may also be assigned internally by the airline. So in your example above HDQBQSK would be located at Scandanavian Airlines headquarters. Not sure what office or function "BQ" is.

[SirXape]

Ok makes a lot of sense. Thank you for your help.