Active Choice Plugin - Annotation Grapes cannot be used in the sandbox

If I upgrade to v2.5.1 from v2.4 my active choice parameters fail with a security issue " Annotation Grapes cannot be used in the sandbox"

My script is a groovy scriptler script with @Grab annotation in it to pull in a library.

Rollback to v2.4 fixes the issue so something in 2.5 or 2.5.1 has broken this. Maybe I am missing a parameter in my scriptler script to not run in sandbox?

Full stack trace attached