Soviet plan for Leningrad if Ladoga supply severed

[TheMarcksPlan]

Were there any contingency plans drafted? My impression from the large volume of supplies via Ladoga and the starvation-level rations in Leningrad is that brutal decisions about military vs. civilian endurance would have been required on a very short timeline - like a few weeks. Were such decisions sketched out? I.e. would RKKA have tried to preserve Leningrad Front and the Baltic Fleet at the expense of the civilian populace? Doing so would perhaps enable the soldiers to hold out a few months, creating time for a relief effort. This would result in mass starvation in the city, of course. Nonetheless the regime was capable of extremely brutal (and probably justified) triage in life and death matters. Enforcing such a decision would be a different matter...