But those were interstellar sleeper ships - so it would make sense for the 2018 improvement in spatial drives to relate to interplanetary flight exclusively. In which case a FTL breakthrough isn't a likely bet. Also, it takes a historian to inform Jim Kirk of the significance of 2018, so it clearly wasn't that big a deal in the grand scheme of things!
Timo Saloniemi
It would make sense to me that the 2018 date might mean something along the lines of an early version of an impulse drive? Or the technology that would one-day form the basis of it.