Ambassador, British Airways; FlyerTalk Posting Legend
Join Date: Apr 2012
Location: Leeds, UK
Programs: BA GGL/CCR, GfL, HH Diamond
Posts: 42,990
Since April 2017 this year WT+ no longer books in to J selling class and therefore any WT+ trip booked with domestic connections will include those connections in ET. Prior to the introduction of CE on domestics a WT+ used to book with J selling class in the domestic flights which was Business UK but not a separate cabin.
If you book a WT+ trip now and wish to upgrade the domestic flight as well as the long haul you would require reward availability in CE for the domestic and have to pay the extra avios and tax.