It's not only GA that does not fly to London by October but fellow Asian airline such as MF, 3U, D7, HX, and most other airline don't even fly to London too. So I bet GA is now following these that do not fly to London now. Hopefully GA and these airlines return or fly to London soon
But those airlines that you have quoted are not national flag carriers such as Garuda Indonesia so slightly more insignificant
D7 Air Asia X have already tried and failed London (STN and LGW) and that has already been discussed in previous threads on a.net.
HX Hong Kong Airlines have previously flown an all business class A330 from HKG to LGW that only lasted for approximately 6 months in 2012, that also failed.
With the recent expansion of China-UK links I am very confident that MF Xiamen Airlines and 3U Sichuan Airlines will both be flying into LHR within the next 12 months.
Garuda Indonesia initially commenced operations to LGW in June 1981 and continued to do so until 2003. Emirates had already stolen the market between the United Kingdom and Indonesia by the time Garuda resumed London operations four years ago and for the small market that remained it wasn't really feasible for them to carry on with a link to LHR and it's more plausible for them to consolidate at AMS for obvious reasons that have already been discussed.
Others have mentioned that GA should have remained at LGW rather than transferring to LHR but in all honesty and I hate to say it but I think that the same consequences would be the same.
It's a shame though that Garuda are leaving the United Kingdom and in particular LHR as I can honestly say that some of my best flying experiences have been with them.
It will be interesting to see if British Airways did eventually resume flights Jakarta, not saying that they will but non the less be interesting if they did announce it as there expansion going East has been very lacklustre over the years.
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