Ok... here is an input from an ignoramus: The whole purpose of evolution is for the jeevas is to realise the Brhman and become one with It/Him/Her by realisation/sayyujja/serving Him/Her/It etc. When after 4 yugas it is found that all the yugas and the relative experiences have failed in the objective, there cannot be any benefit from taking off from the latest stage of evolution. If it was possible to take off from the current evolution, probably there may be no need for mahA-pralaya. So my guess is that new creation will start from the begining all over again (like the single cell unit you have indicated) and may be there may be a subtle or slight change in the tanmatras or primordial elements which will help the new jeevas to have a crack at the mokshA once again.