That's very helpful - thanks, oliver2002. We are only allowed flexible fares (starting indeed from Economy Flex for flights up to 3 hours), I'm not entirely sure whether the 572 economy fare you quoted falls under either a Light or a Classic (which we wouldn't be able to book as per internal SOP) but thanks anyway.

That aside and most importantly, would the TA know what to do if I send them the fare basis you kindly posted?

G