Found a hack to open up the device, based on @sazwl’s guide on YouTube.

1. Unbox the device, allow it to do its updates, then connect device to Google Home app on your phone. I had to use an Android phone as my iPhone didn’t shown the Screen reader option.
2. Check that calendar is linked with utterance ‘Hey Google, what’s my next appointment’
3. Create a new appointment, make sure it is the next appointment with the subject as follows:
   • https://f-droid.org/packages/com.menny.android.anysoftkeyboard/
4. Next, we need to get a keyboard on to the device. The easiest way to do this is to get the Screen reader to make an utterance and read out the URL above, copy that into the clipboard, then force a launch of the internal browser and paste the utterance URL into the browser, download the APK for the keyboard and install it. The steps are:
   • On Google Home app on your Android phone, enable the Accessibility option to enable Screen reader.
   • Go to the device, swiping until the calendar item is highlighted.
   • Make a ‘L’ gesture to invoke the Screen reader and keep swiping until the calendar item is highlighted.
   • Copy the last utterance to clipboard
5. On device, get to Talkback Settings option and double click to get a new menu. Stop the screen reader on phone. Now we need to invoke the internal browser by doing the following:
   • Swiping until you get to Privacy Settings
   • Highlight the URL, paste from clipboard, highlight again and click Open
6. On the F Droid page, scroll down to download the APK for the keyboard, and install it
7. Power cycle the device.
8. Now you have a keyboard. To get to the internal browser again to install more APKs, like a Launcher, do the following:
   • On Google Home app (on an Android phone), enable the Accessibility option to enable Screen reader.
   • On the device, make a ‘L’ gesture to invoke the Screen reader
   • Double click on Talkback Settings to get to the next menu
   • Stop the Screen reader on phone
   • Swipe down you get to Privacy Settings, double click to launch browser
   • Now you can use the keyboard to get to your favourite APK download site
9. To install a Launcher, do step 8 and look for the launcher APK on F Droid using search ‘last launcher f droid’. Install launcher and power cycle.
10. Also, suggest you install a ‘button remapper’ APK to map the ‘-‘ button on top of the device to Back and ‘+’ to Home.
11. For setting up as Home Assistant, follow these steps:
12. Install Fully Kiosk using step 8 – I found an APK on APNPure.
    • in HA, make a new lovelace item on dashboard called ‘clock’
    • if not installed, use HACS to install the ‘kiosk’ add-on
    • Install Fully Kiosk using step 8 – I found an APK on APNPure – make the start URL
      • http://homeassistant:8123/lovelace/clock?kiosk – replace ‘homeassistant’ with your setup
    • Power cycle the device, use the Launcher to launch Fully Kiosk!

Video of end result https://youtu.be/Z9oHF71npKI