Seeking Compensation query – BA Response

[Flyer123]

Dear Forumites,

Was on flight BA0036 on a Business-class return (241) on 27 Aug 2022 from MAA-LHR. The flight was delayed before take-off by 4+ hours and eventually landed 222 minutes late. We were using the lounge facilities in MAA and were there most of the time, so no extra expenses.

I submitted a Delay compensation claim to BA and their response came back as – Your claim’s been refused because although the BA0036 on 27 August was delayed by 222 minutes, only 133 minutes of this delay was our fault.
On the day you were due to travel, Air Traffic Control restricted operations into a block of air space your aircraft needed to travel through. This caused the other 89 minutes delay. I’m afraid this was our of our control and caused unforeseen disruption to our schedule.
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Is there anyway to verify this is true ? What would be my next steps (if any) to get EU261 compensation if I am eligible ?
Thanks in advance all for your inputs.
~Sundar

[JDB]

Unfortunately, it’s very difficult to verify and while the APR say the onus is on the airline, it doesn’t say at which point. If you wish to pursue the matter you will need to go to CEDR or MCOL – reply to the refusal asking, within 14 days, for evidence to support their refusal and that failing the provision of this and/or continued refusal, you will take the matter to CEDR/MCOL without further reference to them.