Sri Aurobindo distinguished three preliminary stages before the attainment of "Supramentalisation" Even these include stages beyond simple Liberation.
(1) "Brahman" - this is basically your simple Liberation state. Sri Aurobindo - as an Adept - attained this in 3 days by just sitting and meditating (like Guatama Buddha!). He was taught a technichue by another yogi (Lele i think his name was) - "observe your mind. You will see thoughts entering from outside. As soon as they try to enter - push them away."
Sri Aurobindo sat down to meditate & lo! found it was so. He pushed the thoughts away each time they tried to enter & after 3 days had attained Liberation & Stillness of the Mind. (obviously here "mind" = consciousness - not mental body a la Theosophy - c.f. yogachara definition of "mind")
This "brahma" stage is clearly equivalent to Da Free John's (AdiDam's) "Sixth Stage of Life". One experiences reality as maya - a superficial play which the Self stands back from. From here I presume one can enter nirvana (if one chooses)
(2) "Narayana" - experiencing the Godhead everywhere. Sri Aurobindo experineced this while in prison awaiting execution for sedition by the British (he was involved in the movement to free India - he was released after a year but some of his comrades were executed). Everywhere he looked (in the prision courtyard) he saw God. The Tree was God. The walls were God. (Narayana is one of the Vaishnavite terms for the personal Godhead)
(3) Overmind - this was experienced some years later in conjunction with Mirra Alfassa - The Mother. Overmental realisation gives the power TO BE God - the power to make a New Creation. Sri Aurobindo and the Mother attained this Power but sacrificed it in order to have a greater attainment - the Supramental realisation. (well - so they claim - I don't know if they really DID attain it - I am an empiricist after all - but i am just presenting the doctrine for all of you to consider for yourself)
In Aurobindo's cosmology by the way - Overmind is transitional between the lower creation and the Infinite Godhead. The Overmind is the realm of all the Gods and Godheads. I suppose it could be indentified with the Gnostic Pleroma and the Kabbalistic World of Atzilut.