OK --
I had to run down some ECO history.
It was actually V4 that had the hardware change for the adjustable BEC.
And yes, if you have adjustable BEC it will show up -- otherwise there isn't any option to change the BEC voltage.
/whew
I was thinking there might be an issue where it showed the BEC as adjustable, but didn't actually do anything.
We started building V4 about 30 months ago, and V5 about a year ago.