I have a hard time believing it means full enlightenment. However nice that result sounds, even logically it can't mean full enlightenment. The force of karma is said to be inexorable. It's hard to imagine how a person's accumulated karma over countless lifetimes can be expunged so simply and instantly. Further, there's possibly a bit of a Catch-22 when it comes to enlightenment which may or may not be relevant. In the Mahayana tradition, part of the bodhisattva vow of compassion is to refuse to exit the cycle of samsara until all beings can attain enlightenment, like the captain of a sinking ship refusing to get into a lifeboat until everyone under his or her command is safe. That is to say an enlightened being will always choose re-birth in order to help beings reach enlightenment, which is counter to the idea of selfishly and individually dissolving and entering buddha-fields and escaping the cycle of re-birth.
My speculative interpretation to make this all work, without any sources to back me up, mind you, is that liberation or buddhahood attained in the bardos through these methods and means may be a partial enlightenment with the effect of slowing and delaying our passage through the bardos and into re-birth, which is inevitable due to either not being full enlightenment and the inexorable force of karma (if there still is karma, there will be re-birth), or the bodhisattva vow to be re-born to continue the work of assisting beings towards enlightenment. Viva la run-on sentence! Whenever I stop Englishing means don't take me seriously.
Delaying re-birth is basically a prolonged suspension in the non-corporeal bardo states, "buddha-fields" or pure lands possibly. This idea of delaying re-birth, albeit not explicitly mentioned, can actually be read into the Tibetan Book of the Dead. After the bardo of ground reality, it is said one enters the bardo of "existence", the third of three, also translated as the bardo of re-birth or "becoming". The bardo of existence is when we most identify with our previous incarnation and when our ego-habit of who we were is strongest. It's the most Dante-like experience and includes opportunities for liberation by recognizing the nature of mind. But as opportunities for enlightenment are missed, the force of karma draws us towards re-birth.
But even still, the book has instructions for "blocking the womb entrance" to prevent re-birth for those who have made it this far without recognition. Again, it's not explained what this means nor what the results of blocking the womb entrance are. I think the implication is that if this person has gotten this far, they are heading for re-birth, it's unavoidable. They didn't have the aptitude or cultivation or practice to recognize the nature of mind. But still these last-ditch instructions to block the womb entrance. Why? Attaining buddhahood or entering buddha lands are no longer mentioned. So maybe it's to delay re-birth for as long as possible.
I wonder if maybe the benefits of prolonged suspension in the non-corporeal bardo states is immense. I wonder if maybe prolonged being in the bardo states infuses karma with the nature of that state, in perhaps an analogy of acclimating to different environments such as altitude or temperature. I'm just making this shit up at this point, by the way. It's not only a non-corporeal state, but a state of non-duality, which is what teachers repeat over and over as the state practitioners aspire to recognize and understand. Non-duality is what practitioners all over the world scratch their heads trying to get their minds around. Our corporeal existences are by nature dualistic separation from enlightenment, the ground luminosity that characterizes enlightenment. All phenomena are pulled out of the ground luminosity into existence by our samsaric, habituated minds of duality, like waves out of the ocean. We can't see the ocean for the waves.
I wonder if maybe more time spent in the bardos can lead to a re-birth with a predilection (seeds, at least) towards higher states of spirituality embodied by the ideals of compassion, wisdom, cultivation and transformation. I think the Tibetan Book of the Dead applies to all levels of practice. The most advanced practitioners will attain realization early in the bardo states when opportunities are most potent, and will remain in the bardo states for longer periods. There is precedent for this idea in the literature, but I'm not arguing anything so I'm not going scrounging for cites. Lesser practitioners can more likely attain recognition in the existence bardo and resist re-birth for shorter periods. Those who only hear the instructions for blocking the womb entrances and are able to execute them can still benefit with certainty of finding themselves back on the path in their next life.
As for how long beings remain in the enlightened states of the bardo, it's tricky to say because time is a convention of our physical world. Within the experience of the bardo, time may be totally irrelevant. From the perspective of the physical world, I just have an anecdote my cousin Audrey mentioned. We didn't discuss this at length, this is just my thinking about her once reporting one of her daughters telling her when she was still an infant something like "don't worry, I'm your mother", the implication being clear to us that she was the reincarnation of Audrey's mother who died in 1993, some 11 years before the daughter was born.
Initially, I questioned the gap of time between Audrey's mother's death and her daughter's birth because my understanding was quite primitive. Now, it's not outrageous. Audrey's relationship with her mom included complications any mother-daughter relationship can have, but her mom's effect on her especially after death can be seen as that of a spiritual mentor. It's not outrageous that her mom was able to remain in the bardo state for that long in our measure of time until she could let karma bring her back specifically as Audrey's daughter. I'm not saying I absolutely believe this or that it has some great meaning to how Audrey or her daughter should live their lives. Just that I'm sure stranger lore has been told.
It may even not be too outrageous to question the parinirvana of the Buddha. It is said that when the Buddha died, he entered parinirvana: total, full, complete, absolute enlightenment, melting into the ground energy and reality of the universe, escaping the cycle of re-birth never to be born again.
First of all, when I said that I believe in reincarnation because it resembles cycles that occur in nature, there is nothing unnatural about parinirvana just because it breaks the cycle. That's not the reason to question the Buddha's parinirvana, which theoretically could be a character of nature. After all, reincarnation assumes the existence of people, and people haven't always existed and the continued, perpetual existence of humans is simply not something that can be assumed.
I'm saying the teaching of the Buddha's parinirvana may have been a sham to give humans a goal, because
The Buddha escaping the cycle of re-birth doesn't make sense because of that boddhisattva vow of compassion. It just doesn't make sense that the Buddha of infinite wisdom and compassion would enter parinirvana, unless he couldn't avoid it, when he could continue to benefit beings by continuing in the cycle of re-births. But such an enlightened being isn't continually re-born uncontrollably like we the rest of us are. The Buddha can choose selective re-births when moments are most opportune to the maximum benefit to humanity. Such as when the people who were living on what we call the Tibetan plateau became ripe to receive and develop the dharma. Tibetans consider Padmasambhava, the founder of Tibetan Buddhism, a second Buddha, a follow-up to the first, but I wonder if maybe Padmasambhava wasn't the actual re-incarnation of the actual Buddha after some 12-13 centuries. Stranger lore has been told.
