IntelliJ Idea 2020.3 built-in kotlin plugin 1.4.10 vs kotlin language 1.4.21

Why IntelliJ Idea 2020.3 built-in kotlin plugin 1.4.10 (including compiler) is older than the latest kotlin language release (including compiler) 1.4.21  from https://kotlinlang.org/releases.html ?

Does IntelliJ Idea 2020.3 built-in kotlin plugin 1.4.10 (including compiler)  support features of 1.4.20, 1.4.21  (like Supporting new JVM features, like string concatenation via invokedynamic, ... ?