Mapping optional arrays of objects to arrays of objects

I have an input schema that contains some optional arrays of objects in one format that I need to map to a target schema with an array of objects in another format.

The problem I am having is how to get the Mapper to map the array if it is present and ignore it if it is not. For example, my mapping table expression for one field below works fine for documents where the Address element is present but causes an error if it is missing.

jsonPath($, "$MatchUpdatePartyPayload.Address[*].NonStandardUS.Line1") 

Thanks,
Robert