It looks like the new EU compliant trailer from Sovereign has a rethink around wheel housings and lights. If I recall correctly there is a new obligation to have permanently mounted (waterproof?) lights and reflectors. You can see something here in the way for forward mounted lights (or reflectors?) and side reflectors.
You can also see something else here – better road-spray management. There is a permanently mounted wheel flap and I’d say that the mudguard itself looks more enclosed than the preceding model.