In my understanding of their meaning, the "five heaps of wood" also known as The Five Aggregates, is a schema explaining phenomenological makeup of our subjective existence. In other words, everything that we can ever be aware of, is like a soup made from the following types of ingredients:
- Raw stimuli (rupa)
- Feelings (vedana)
- Notions (samjna)
- Memories (samskara)
- Interpreted Experiences (vijnana)
This may not be very precise from modern cognitive science perspective, but that's not the point. The point is to show how our entire world with its seemingly infinite complexity and troubles can be simplified to only a few ingredients. When one sees the world in terms of these ingredients, it seems almost comical to take the usual drama seriously. This is the true meaning of Satipatthana practice, to switch one's attention to a different descriptive framework, in order to enable emotional detachment and gain control over one's mind.
The way our subjective existence develops from scratch is explained in the teaching on Twelve Chainlinks, or nidanas:
- Initial Non-differentiation (avijja)
- Naive Imprinting or Accumulation of Memories (samskara)
- Naive Interpretation (vijnana)
- Naive Identification (namarupa) and Conceptualization (samjna)
- Naive experience of ourselves as a "house with six doors" (salayatana)
- Naive experience of "contact" with "external object" (phassa)
- Naive association of internal feeling as something coming from the contact with an external object (vedana)
- Craving for that experience (tanha)
- Obsessing and pursuing of that experience (upadana)
- Conflict with the world and resulting individuation (bhava)
- Self-identification with the living organism (jati)
- All kinds of trouble (jaramarana)
Again, I'm not sure I got all the details 100% right, but the main point is that subjective experience develops from complete non-differentiation -- to a full-blown individuation, through a series of steps that build on one another. Generally speaking, we learn to recognize and differentiate our experiences, until we develop attachments to some of them, and from this attachment comes a sense of conflict with the world which eventually arises as a notion of separate "I". Also note how four of these refer corresponding skandhas.
Because this process is entirely pre-conscious, we're only aware of its result - the experience of being a sentient being living in the world. We are not aware of the mechanisms at play, because we (=our experience of ourselves) are a result of this process! However, this process comes with a payload of trouble, due to the tendency of reification and conflict built into it's very foundation.
Enlightenment involves gradual liberation from the limitations of experience imposed by this process. This liberation is done through detachment from "realities" generated by the process (so called "self" and "world"), through increased awareness of the process' mechanisms and their implications, and through learning a new, higher, mode of perception that does not involve naive reification of our interpretations as the reality. As this Enlightenment progresses, we start seeing through the magic tricks of the process. In this sense we can say that the twelve steps of individuation are getting undone:
"Now from the remainderless fading & cessation of that very Ignorance comes the cessation of [Naive Imprinting]. From the cessation of [Naive Imprinting] comes the cessation of [Naive Interpretation]. From the cessation of [Naive Interpretation] comes the cessation of [Naive Identification and Conceptualization]. From the cessation of [Naive Identification and Conceptualization] comes the cessation of [Us-As-House-With-Six-Doors]. From the cessation of [Us-As-House-With-Six-Doors] comes the cessation of [Naive Experience of Contact]. From the cessation of [Naive Experience of Contact] comes the cessation of [Naive Attribution of Feeling]. From the cessation of [Naive Attribution of Feeling] comes the cessation of [Craving]. From the cessation of [Craving] comes the cessation of [Obsession/Pursuing]. From the cessation of [Obsession/Pursuing] comes the cessation of [Individuation]. From the cessation of [Individuation] comes the cessation of [Self-Identification-With-A-Living-Organism]. From the cessation of [Self-Identification-With-A-Living-Organism], then aging & death, sorrow, lamentation, pain, distress, & despair all cease. Such is the cessation of this entire [burning] heap of stress & suffering."
According to my teacher, the reason we learn Five Skandhas and the phenomenological mode, is to detach from the original "view" of the world, to stop assuming that our interpretation is reality. In order to facilitate this detachment we learn a different "view" (also known as "the raft") - the view of Five Skandhas etc. As we practice Satipatthana and get in the habit of maintaining this phenomenological view, we detach from the original naive view of the world and learn to control our mind. But this second view is not the ultimate reality either! It is only a provisional tool, designed to help us overcome our naive attachment to the first view. Once we develop enough insight, we realize that all views are just that, views, or interpretations - and none of them can be called primary. This liberation from all views, in practice, not just conceptually, leads to emergence of a new way of perception/cognition that in some sense can be called "multidimensional" or "transconceptual".
This transcendental perception is immune to reification, immune to attachment, and therefore immune to any sense of conflict and suffering.
Finally, to answer your question: with achievement of that transcendental perception, "the raft" is no longer necessary, so the Five Aggregates model is no longer relevant or applicable. We could certainly come back and say that Raw Stimuli remain more or less the same, that Feelings are no longer attributed to an external object, that Notions lose their solidity, that Memory Imprints are purified, and that Interpreted Experience is transcended - but this would be dragging ourselves back into confines of a view. So in this sense, Five Aggregates disappear, or are recognized as "empty":
Bodhisattva Avalokiteshvara, performing meditation in the deep Prajna-Paramita realized thus:
There are Five Heaps, and they by their nature are empty.
Hey Shariputra, rupa is emptiness, and emptiness if rupa. Emptiness is not different from rupa, and rupa is not different from emptiness. What is rupa is emptiness, what is emptiness is rupa. The same is true of Vedana, Samjna, Samsara, and Vijnana.
Shariputra, all phenomena have the character of emptiness.
They have no beginning and no end.
They are not pure, neither are they impure.
They do not decrease, neither do they increase.
Therefore, in emptiness, there is no Rupa, no Vedana, no Samjna, no Vijnana
This is why Buddha's subjective experience is called "indescribable" - because it actually transcends any single view.
Now, on intermediate stages of development, we may either catch a practitioner at a phase when he or she is squarely focused on seeing everything in terms of The Five Skandhas... or the next phase, when he or she is beginning to see the approximating/conventional nature of concepts... or the next phase, when he or she is beginning to lose solidity of any single view.
(I realize the above is far from being an obvious interpretation of Buddhism. However, this is what I've got from my decades of study and practice, under several different traditions, with live teachers, reading books, and meditating. So far, this is the only interpretative framework that fits with all sources and all traditions of Buddhism I have ever encountered. I don't claim omniscience, but I claim that I did my homework. You're free to ignore this, or you can try this on as a dress and see if it fits.)