However, the 2M probes ended significantly heavier than intended and engineers also ran out of time to conduct drop tests of the lander, so that part was abandoned which left only the orbiter.
In contrast, the 2M probes proved to be substantially heavier than initially predicted, and consequently, engineers were unable to carry out the necessary crash tests for the lander before time expired, causing them to abandon that aspect, leaving only the orbiter as a result.