Holdsworth (now owned by Falcon) are probably bought from an open mould in China as Falcon long ago abandoned the high end market so I can't imagine they've suddenly gone from BSO's to a full on product development team with composite specialists overnight. Not nececeraly a bad thing*, but you may well find them somewhere else too.
Dunno what else on the site is open mould (IIRC some of the old TT and track frames were open mould as it was cheeper to design a bike, then sign over the rights to the factory than pay for the tooling outright, so a Planet-X bikes really did appear in the TDF time trials with other stickers on them). They're pretty open about what's their design and what isn't, but I don't think there's the same frame under different brands on their site?
*infact it's good, means they keep costs down by spreading it amongst several 'brands' who buy the frames, and in reality is it any different to how frame builders used to work buying tubesets and luggs, now they just buy the moulds? And they may well ask for different layups as well