It has been happening to a lot of us over the last few months. Apparently something to do with not taking the required number of bmi flights to acquire the necessary status points!
Goodness me, how could that be - when they ceased flying some months ago.
Fear not, although your BA Gold is secure, you might yet win the prize for the latest issued bmi "renewal pack"
http://www.flyertalk.com/forum/bmi-d...ved-today.html