The 7 or according to some scriptures 5 chiranjeevis continue to guide and help humanity according to the intuition they receive from Above and in the domain of their working. These and other seers have been helping the earth move forward through all the perils and disasters towards the long foreseen golden age. They act from behind the scene by helping, guiding subtly and inspiring those destined for the Divine Work as well as by pushing people and forces behind the material veil.
They are actually chiranjeevis (living forever) which means that they will live till the end of the cycle of the four yugas. Immortals remain until the Mahapralaya when everything is taken back, absorbed into the Consciousness of the One. The Supramental Creation means coming out of the cycle of the four yugas completely. It is to enter into a new creation that is freed from beings of the Overmind and below (the gods and the chiranjeevis). Then their great role in keeping the cycles afloat and preventing humanity from sinking completely into the darkness will be over. In all likelihood they will be absorbed into the Divine.
Of course they can participate in the New Creation but for that they have to take a human body and enter the evolutionary process again.
Affectionately,
Alok Da