Kotlin 1.2 Not Available in Kotlin Compiler options


I have a project that requires Kotlin 1.2. However, this is not an option on the language version option in Kotlin Compiler Settings. 

I have the latest IntelliJ Ultimate version and the latest Kotlin plugin version.

I tried to downgrade the Kotlin plugin version but it's not supported for this IntelliJ version. 

Can someone help me? 

Thanks :)