Since Rock actually didn't answer your question despite 4 posts, I thought I'd give it a try. +10 years experience in the industry should qualify me as an "oil-professional"
Your concern about heavy oil also in the shallower sands is very valid, the general trend is that the shallower you go, the heavier the oil gets. In addition the lower temperature leads to higher viscosity and lower flow rates. I would be very surprised to see lighter oil further up. However, the wells drilled last year showed much lighter oil not very much deeper, so there is some mechanism here related to migration paths and sourcing that POE probably hasn't figured out, or at least not communicated to the market.
As for the almost immediate water breakthrough, that just tells us that the well was drilled very close to the OWC, and that the accumulation at the A4 level is very limited. I would assume that also the other sands will water out rather quickly, we will know that fairly soon.
What we don't know, or at least not I, is how far updip the formations extend until they seal against the faults. That decides the size of this pool. If the other sands water out as well, they will probably be able to drain this pool from the twin well to be drilled, which will be placed updip. That one will also target deeper sands, which might have lighter oil and higher flow rates.
As I've said before, this does not seem like a basin where you make large discoveries, the closures are small to start with, and they are not filled to spill. The good thing is that with 3D seimics they should have a pretty good hit rate, the wells are cheap and the net-backs are world class.
Happy to answer any further questions you might have.