Cautious Optimist - I agree the fares are not high (I flew one way for less than £50 !) but Eastern must be burning through large quantities of subsidy cash if they need to sell seats at fares comparable with 2nd class advance booked train fares to get a non trivial load factor. I can only guess that prices are this low because there is a desperate need to show something productive is being achieved.
One should be seeing a material difference in price when booking 2 days in advance... with separation of those who value time versus price. If that can't be achieved in the autumn, it shows there just aren't enough people to need the air route to LCY