Its an educated assumption, since the Bren 2 BR (308 full auto) existed first and this is a modified version of it for military sale would you design a completely new upper/lower combination that couldn't take full auto parts or would you just throw a semi auto selector and trigger into the parts you already make.
Watch the video in post #1 14:17 He says the staff are pushing for a civilian market variant, not a civilian market version exists.
Oh and the full auto FRT for the Bren 2 includes the 308 model where as the Bren 2MS NR FRT lacks the 308 model.
Realistically no one here can really give you the definitive answer you're looking for but also no one can show you a Bren 2 BR and PPS that are functionally different to the point where you couldnt just toss a full auto trigger pack onto it because they likely don't exist outside of CZUB's factory or military hands.