Hide/Make DFF mandatory based on PO document type

Summary

Requirement is to make DFF mandatory at PO header for type lookup code as "Contract Purchase Agreement" only

Content

The requirement was to make a DFF mandatory (PO Headers) for Contract Purchase Agreement only. We have achieved this requirement through personalisation by using following EL expression -

#{bindings.TypeLookupCode=='CONTRACT'?true:false}

Note - same expression can be used to hide the segment

Is there any other method to achieve the said requirement as personalisation may get removed post upgrade?