With LG using the MT1862AN chip since July 2015, it wasn't too much of a stretch to guess that Samsung would eventually come around and start using it too.
(On a more general tangent).
At this point, I don't even know where to start in speculating when the next Mediatek chip will be released. Whether (hypothetically) an "MT1862BN" revision or a new "MT1842N" series (extrapolating).
Mediatek's web site has very little to no insightful information, other than general marketing type stuff.
From the general trend over the past few years, it seems like LG and Samsung have been cranking out a new drive model every 12 months or so. This is probably also reflective of Mediatek cranking out new chip series/revisions every 12 months or so, almost like clockwork.
If it continues to run like clockwork, then perhaps LG's engineers already have their hands on a new (hypothetical) "MT1862BN" or "MT1842N" chip, and are already at work designing a new drive and writing a new firmware for it, ready to be manufactured this coming July 2016 ?