...
ExternalIdsServiceV2 {
listExternalIds(studyId, subStudyId, offsetBy, pageSize, includeDeleted)
createExternalId(externalIdObj)
getExternalId(studyId, subStudyId, externalId)
updateExternalId(externalIdObj)
deleteExternalId(studyId, subStudyId, externalId)
deleteExternalIdPermanently(studyId, subStudyId, externalId)
// These would update an add an associate record between Account and SubStudy with an account ID
assignExternalId(studyId, subStudyId, externalId, accountId)
unassignExternalId(studyId, subStudyId, externalId)
}
...