Default value of a assignment DFF based on EFF

We have a requirement to default an assignment DFF based on Job EFF.

Assignment DFF should default to a value of Job EFF and Job EFF has a default constant value defined.

We are unable to achieve this at the DFF level with defaulting type as SQL and trying to achieve this through AutoComplete rules.

However, we don't see the supported Job EFF fields to extract in autocomplete rule.