Correct way to update Railway Vars in a production service

Question

Does Railway expose a "correct" way to update a production environmental variable programmatically so that it's live in the container service?

For background - We have a sandbox image ID which is built when a merge to main takes place. This is an indempotent image ID so the API service in railway needs to be aware of this

I'm finding myself doing this which i I think is brittle beacuse of race conditions between deployment + Github Actions

```
      - name: Publish sandbox image
        id: publish
        run: |
          set -euo pipefail
          RAILWAY_ARGS=()
          RAILWAY_FLAG_INPUTS="${RAILWAY_TOKEN:-}${RAILWAY_PROJECT_ID:-}${RAILWAY_SERVICE_ID:-}"
          if [ -n "${RAILWAY_FLAG_INPUTS}" ] && { [ -z "${RAILWAY_TOKEN:-}" ] || [ -z "${RAILWAY_PROJECT_ID:-}" ] || [ -z "${RAILWAY_SERVICE_ID:-}" ]; }; then
            echo "RAILWAY_TOKEN, RAILWAY_PROJECT_ID, and RAILWAY_SERVICE_ID must all be set together." >&2
            exit 1
          fi
          if [ -n "${RAILWAY_TOKEN:-}" ] && [ -n "${RAILWAY_PROJECT_ID:-}" ] && [ -n "${RAILWAY_SERVICE_ID:-}" ]; then
            RAILWAY_ARGS+=(--railway --railway-service "${RAILWAY_SERVICE_ID}")
            # Update env vars without triggering a Railway deploy during image publish.
            RAILWAY_ARGS+=(--railway-skip-deploys)
            if [ -n "${RAILWAY_ENVIRONMENT:-}" ]; then
              RAILWAY_ARGS+=(--railway-env "${RAILWAY_ENVIRONMENT}")
            fi
          fi
[truncated]

- name: Redeploy Railway service
        if: ${{ env.RAILWAY_TOKEN != '' && env.RAILWAY_PROJECT_ID != '' && env.RAILWAY_SERVICE_ID != '' }}
        run: |
          set -euo pipefail
          LINK_ARGS=(--project "${RAILWAY_PROJECT_ID}" --service "${RAILWAY_SERVICE_ID}")
          if [ -n "${RAILWAY_ENVIRONMENT:-}" ]; then
            LINK_ARGS+=(--environment "${RAILWAY_ENVIRONMENT}")
          fi
          railway link "${LINK_ARGS[@]}"
          railway redeploy --service "${RAILWAY_SERVICE_ID}" -y
```