Richard Deakin, CEO, NATS, ... muttered stuff about upgrading resilience.
Upgrade ? Yes my first thought.
Resilience? Yes my second thought. Resilience to previously unanticipated airspace incursions perhaps?
Lots of those making the headlines recently.
Flight planning server fell over, did it? What sort of significant traffic provides no flight plans?
Flight_Plan=Null would need some error handling in the code, throughout the entire 4 million lines, not just the bit some bright spark upgraded in isolation yesterday
Or maybe they hadn't been upgrading resilience, but it's done now
Just a couple of thoughts ...