Postcodes - how to randomly generate postcodes and blank postcodes

Hi There

Issue 1. I have a JSON schema which contains a postcode field that uses the postcode data type. However in certain scenarios I would like it to return a blank value without the actual field being removed from the schema in the output. Can this be done? if so how? I would like this to be done without using a custom list as I do not want to manually specify postcodes.

Issue 2. This JSON schema contains a country field along with a county (state) field. I have noticed that certain countries do not have counties (state)/postcodes however I noticed when this is the case, the county (state)/postcode field is removed from the JSON output, is it possible for the county (state)/postcode field to return a “” blank value rather than the field being totally removed from the output?

Issue 3 - I am using date field types for a start date field and an end date field - Is there a formula that can be used to ensure that the date for the start date field always has an earlier date than the end date field?