The reason the a/c were not repainted is quite simple. BMI were under going the slow process of rebranding from british midland to bmi when the devastating events of 9/11 left the company nearly going under. Non of the aircraft we were flying and over a year old had been changed, it was planned to be done as and when the a/c went in for their major checks. Obviously the financial problems experienced ever since have left that process as not vital. All the other a/c that have the new colours were delivered just before or since then and the rest have gone.
And to answer why the 321's are being replaced; cut capacity increase cost especially now the LO CO operaters compete heavily on those routes from various airports in the South East and re focus the airline to mid haul destinations.
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