Elevation in metres everything else in miles/feet

I decided last week to change my units of measurement from metres to miles.

I went into Garmin Connect>Settings>Display Preferences and selected Statute UK as my preferred units of measurement.
I then went into Setup>System>Units on my Forerunner 610 and altered the units there (including elevation).

After I made the changes I did 2 runs which have now been uploaded to Garmin Connect. Both activities still show the elevation in metres although everything else is now in miles or feet.

I've checked the 610 and it still says feet for elevation and Garmin Connect is still showing Statute UK for the units.

What other step have I missed to change the elevation from metres to feet?