This is the ValueSet that contains all the codes in Requirement Change Indicators (http://hl7.org/ehrs/uv/phrsfmr2/ValueSet/change-info) and Requirement Change Indicators (http://hl7.org/ehrs/uv/phrsfmr2/ValueSet/change-info). E.g. what you have to deal with if you get resources containing codes in either of them