I think it looks like a good and logical layout.
Per the diagram provided by airpearl in post 48, it would seem that J class will only have to wait whilst Y pax in 6 rows (34-39) disembark (a small inconvenience).
One would assume that pax in the first 11 rows (24-34) will either be hald back for J to disemark, or directed to the lower floor via the front stairs, so as to not inconvenience J pax.
As described in an earlier post, this layout enables compatability with the DXB
layout, where premium pax load via the upper floors only, with minimal disruption on arrival.
For J class pax, the positive thing from this layout is that with fewer J seats, the bar area should be less packed.
For Y class the ability to have upper deck seats and a 2-4-2 layout is a big positve.
These show as toilets only on the new layout, with no showers. These must be rather large toilets - as they have a lot of room there - or perhaps can fit 2 x toilets into each side? either way another positive for the Y class on the upper deck (either big spaceous toilets, or lots of them!)
So all in all, quite a good layout for all classes in my opinion!