It's a damp leased Astraeus 757 which has been there for well over a year now. Generally serves Almaty and Bishkek. Originally there were two of them but BMI managed to wriggle out of one airframe under a 'contractural dispute'
It was always a risky deal with reliability issues of older airframes. The pilot Union saw an outside airline operating previous BMed/BMI A321 routes as a direct threat to the SCOPE agreement and dug their heals in, which I don't think the managerment foresaw coming.