Section 9 DC Terms and Conditions

9.Length of programme
1.In the event that the Diamond Club programme should be closed, bmi shall use every reasonable endeavour to publicise at least three months’ notice of the closure of the Diamond Club programme. At the end of that period members shall no longer be able to earn Destinations Miles or Membership Status Miles, redeem Destinations Miles or utilise Membership Status Miles nor shall the member be entitled to any benefits under the Diamond Club programme other than flights or other services already redeemed but not yet utilised prior to the end of such period.

I think a legal remedy might be difficult