This is little inconsistent. Kotlin is well under development since 2010 and was published in 2011 or earlier, so it is already a 2 or 3-year-old project.
This doesn't matter much, v1.0 is a very important milestone because very little will be written about the language before then. Also, nobody will consider using a pre v1.0 language in production, no matter how many years it was in development.