throw new Error("Unknown UI mode"); - when selecting Vertical Clock as default clock.

I updated to the latest Settings App (v0.27), Booloader (v0.27) and Vertical Clock (v0.9)
Whilst looking at another issue I set default clock to Vertical Clock and when I came out of settings
I got the following error.
In this state the Watch is locked, none of the buttons or touch controls will return you to the Launcher or settings App. The clock continues to run buts thats all.

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         |_| espruino.com
 2v09.90 (c) 2021 G.Williams
Uncaught Error: Unknown UI mode
 at line 31 col 38
    throw new Error("Unknown UI mode");
                                     ^
in function called from line 5 col 1952
...HRM=[];}drawBPM(HRMstate);});Bangle.o­n('touch',function(button){if(b...
                                      ^
at line 6 col 325
...PSPower(1);}else{eval(clockApp);delet­e clockApp;}
                                       ^
>