Changes to Instructs Home Office downstream systems. Note: Use of the term 'instruct' avoids any confusion with existing business terms, such as 'notification' and 'direction', which are not overly descriptive to the Home Office.

added the new APPEAL_REQUESTED enum value to the request property messageType

added the pattern ^(?:\d{4}-\d{2}-\d{2}|\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(?:\.\d+)?Z)$ to the request property challenge/challengeSubmissionDate

the challenge/challengeSubmissionDate request property format was generalized from date-time to no format

added the pattern ^(?:\d{4}-\d{2}-\d{2}|\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(?:\.\d+)?Z)$ to the request property deadlineDate

the deadlineDate request property format was generalized from date-time to no format

endpoint added