Personally, they will have a long range missile within a year or two. Many of these think tanks do not have information that is not available to them.So they make a “educated guess:.
That would be my guess, they will have the delivery system
at the same time as the weapon.
Even if they don’t, I would expect intermediate range missiles launched from merchant ships, probably disguised
as oil tankers. (Who says they don’t have a sense of humor.)