HGV height/width update state not functioning

[TimMcCauley]

And on second call with HGV settings enabled the request fails with

react-dom.production.min.js:232 Uncaught TypeError: e.hgv.shippedHazardousGoods.join is not a function
    at actions.js:191
    at actions.js:292
    at Object.dispatch (index.js:8)
    at dispatch (<anonymous>:1:28545)
    at Object.n.handleFetchIsochrones [as onClick] (SearchControl.jsx:122)
    at e.exports (_apply.js:20)
    at e.exports (_baseInvoke.js:22)
    at e.exports (_apply.js:23)
    at _overRest.js:36
    at Object.onClick (Portal.js:113)