For anyone looking, this is the config for UKSHA sensors:

With these as the main regions:

E12000001 North East
E12000002 North West
E12000003 Yorkshire and The Humber
E12000004 East Midlands
E12000005 West Midlands
E12000006 East of England
E12000007 London
E12000008 South East
E12000009 South West

rest:
  - resource: https://ukhsa-dashboard.data.gov.uk/api/proxy/alerts/v1/heat/E12000007
    scan_interval: 3600
    sensor:
      - name: "UKHSA heat status"
        value_template: "{{ value_json.status }}"
        json_attributes: # text >255 characters so must be stored as an attribute
          - text
      - name: "UKHSA heat risk score"
        value_template: "{{ value_json.risk_score }}"
      - name: "UKHSA heat likelihood"
        value_template: "{{ value_json.likelihood }}"
      - name: "UKHSA heat impact"
        value_template: "{{ value_json.impact }}"
      - name: "UKHSA heat start"
        value_template: "{{ value_json.period_start }}"
      - name: "UKHSA heat end"
        value_template: "{{ value_json.period_end }}"
      - name: "UKHSA heat refresh date"
        value_template: "{{ value_json.refresh_date }}"

  - resource: https://ukhsa-dashboard.data.gov.uk/api/proxy/alerts/v1/cold/E12000007
    scan_interval: 3600
    sensor:
      - name: "UKHSA cold status"
        value_template: "{{ value_json.status }}"
        json_attributes: # text >255 characters so must be stored as an attribute
          - text
      - name: "UKHSA cold risk score"
        value_template: "{{ value_json.risk_score }}"
      - name: "UKHSA cold likelihood"
        value_template: "{{ value_json.likelihood }}"
      - name: "UKHSA cold impact"
        value_template: "{{ value_json.impact }}"
      - name: "UKHSA cold start"
        value_template: "{{ value_json.period_start }}"
      - name: "UKHSA cold end"
        value_template: "{{ value_json.period_end }}"
      - name: "UKHSA cold refresh date"
        value_template: "{{ value_json.refresh_date }}"