Even so, thank you, Seng Kiat. You probably feel, why I am collecting the different statements about ceto-vimutti: the different references are confusing and sometimes even slightly contradicting itself: one reference says that ceto-vimutti means skill in arupa-jhana, another that even rupa-jhana makes that qualification, another says high level of BrahmaViharas do that job – and then there is a Sutta, where the Buddha says that only panna-vimutta and the ubhatobhaga-vimutta have completed that what should be done, all others have still to practice. The discussions here helped me to understand that there are different levels of ceto-vimutti in the Suttas; there are not different levels of panna-vimutti to my knowledge. Panna alone can have different depth and extent, but panna-vimutti means only one definite thing.
Seng Kiat, you seem to be knowledgeable; it may be of some interest for you: only recently, after 45 years on the Dhamma path, I came to the surprising conclusion that the Buddha originally did not teach intuitive insight into 3 characteristic of everything – anicca-dukha-anatta ti-lakkhana (= that, what is so central in modern ways of insight practice). He taught to awake and rouse up the sanna-perception of anicca-dukkha-anatta of everything. Only after the Parinibbana of the Buddha the areas of panna-wisdom were rapidly enlarged, deepened and developed into Theravada and its Abhidhamma. I have still respect for these later additions, even knowing that it is not original. Todays ‘vipassana’ insight practice helped so many.