Using the QRH EO LRC values for mach at mid weights (very high weights of course not permitted under the 140min) I'm getting a TAS of around 390-400kt... I get close to his figure if I take his diversion distance and factor it by 14/18'ths. So I don't know whether the operator has chosen to use a reduced speed figure to draw 3 hour circles which are compliant with the 140min figure. Hence my question...