Apologies for coming back to this thread again but I thought I'd drop in an update in case it's of use to anyone thinking about integrated DVB-T.
B&O UK are absolutely clear that if you have the integrated DVB-T module installed on a BC6 or BV7 you will lose one STB controller. They say the reference in the manual to accessing STB-C on the BC6 via V-AUX is incorrect. You lose one of the two STB-C options on a BV7 (I guess you will also lose one on BV8, too).
The BC6 still has the STB blaster output socket and shows all the STB menus after the DVB-T module is fitted but they say the STB-C is not active - unless anyone knows otherwise.
This raises another question. Losing the STB facility when you have Freeview on-board is not a huge problem, I suppose, but do you lose the option to control an external STB if you have the DVB-S or the DAB module fitted in a BC-6?