An interesting topic for me, this one. I have one rear wheel getting a bit warm too. It's variable - some days just a bit warm, others it's hot with a brake smell. It appears to be the EPB side of things as I note that the other rear wheel has a tiny bit of warmth (perhaps more than the fronts do which is the axle one would expect to be warmer from normal driving).

I have it booked in with my indie and in the meantime I'm trying to avoid using the EPB by parking on level ground where possible so that the parking pawl is sufficient to prevent inadvertent movement. Obviously, if on a slope then the EPB would be used. If I can take my foot off the brake and it doesn't roll then the EPB is left off.

Only problem - there's a 2 week wait until the garage can deal with it. Fingers crossed it lasts that long.

I'm steeling myself for the cost of a new EPB module and if it's less than that then happy days.  2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed