In RoW, Nightblood drinks in investiture until it is satiated, or filled. Does Nightblood leak investiture, and will be able to absorb more in the future, or is it now 'full', and doesn't have the power to drain investiture like it used to? If it does leak investiture, how long until it is powerful again? The foreshadowing seems to indicate there is a lot more in store for Nightblood, but now that it is full, I wonder how it will operate.