In the late 1980s Moscow Metro design bureau, Metrogiprotrans started to develop a set of projects that would bring rapid-transit beyond MKAD, using a system of tracks raised above ground.

Special rolling stock had to be developed to serve the line, as it would have to be resistant to the harsher climate elements and be able to negotiate sharper curves.

The main problems arose from finances, as the design was originally planned to be cost-saving; however, the BLLM turned out to be more expensive than conventional Metro lines.

First, improvements had to be made to the faulty new trains, as they required immediate and unforeseen refits; in addition, despite the sound barriers, further noise reduction works had to be carried out on the tracks themselves by repairing their joints.

Despite the criticism, the Moscow Metro continues to put forward several expansion programs for the BLLM, the first one of which is to place proper reversal sidings north of the station thus separating the terminus platforms into northbound and southbound roles; at present this is announced for 2010.

After the completion of that there was initially a planned northwestwards underground extension towards the terminus of the Kaluzhsko-Rizhskaya line, Novoyasenevskaya with two new stations: Lesoparkovaya and Bittsevsky Park, which opened on February 27, 2014.

After the SL's cancellation, there have been concerns that BL's fate could be much worse, as there are arguments that it would be more practical to disassemble the line and replace it with two-three station extension of the STL.