Even though SN is using the same seat platform as LX, they won't be using the same config. Instead of LX's 2-2-1, 1-2-1 layout, SN is going for 2-1-2, 1-2-1. As well as some other differences here and there, the most noticeable one being the new RAVE IFE platform and the centre console for the double seats will be angled.
Also for those who are wondering, SN will be retaining the same number of seats in both classes.