Take a guess...
If you really think about it, the LC is really being released this year, since it does go into production in December.
Next year could be: LC launch, LS redesign, NX MMC, RC MMC and RC-C, RXL, and CT redesign.
Besides that I don't see why that is such a big deal for Toyota to handle many model updates in one year. An LC and LS in the same year is just fine, plus what is intended.
I only mentioned this, as in having recently read silly excuses on a major Lexus forum that the new LS should be delayed to 2018-19 to leave next year for the LC, as if there are no resources to not have both of them be released months apart.
Stupid reasoning, when pushing that car back any further will mean it also encroaches on, ES, GS, GX, UX, IS, LX, and RC/NX redesigns/launches through 2020.