Update DFF when field value changed

Summary:

I have a req line DFF with an LOV, the SQL restricts the LOV based on :{PARAMETER.RequesterId}, this is working fine.

The customer doesn't want to use :{PARAMETER.RequesterId} which is set on entry to the req form, instead they would like it to be driven from the requester entered in the delivery section as the users use this field to change the requester.

Can this be achieved? Partial triggers? Form field triggers?

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