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Migration guides

Get started with your migration with a set of guides and instructions.

As the e-Referral Service API evolves, endpoints are reorganized or upgraded. When this occurs, the old API endpoint is deprecated and removed.

This page contains information you need to know when migrating from deprecated versions.

Migrating from HSCN/CIS1 to APIM/CIS2

Migrating from FHIR DSTU2 to FHIR STU3

Migrating from the send for triage endpoints to the book/defer endpoint

Migrating to the FHIR R4 retrieve attachment endpoint

Migrating to the FHIR R4 upload attachment endpoint

Last edited: 14 August 2026 11:53 am