05-13-2016 12:13
05-13-2016 12:13
05-20-2016 01:41
05-20-2016 01:41
There's no way to manually configure these settings so you'll have to live with (or ignore) Fitbits use of average data for weight and height in this regard. Whether there's a suggestion on the Feature Request board here that you'd be interesting in voting for as an alternative, I don't know.
Mike | London, UK
Blaze, Surge, Charge 2, Charge, Flex 2 - iPad Air 2, Nokia Lumia 925 (Deceased), iPhone 6
Take a look at the Fitbit help site for further assistance and information.