Hopefully if you wanted a British-made Brooks saddle for your bicycle, you ordered it already. If not - and you're in the UK - you're out of luck for the time being.
Seems that while the saddles are made in Britain, they're shipped to customers from Brooks's logistics centre in Italy. Brexit-related troubles have meant they've stopped taking UK orders:
UK Shipping Notice
Seems that while the saddles are made in Britain, they're shipped to customers from Brooks's logistics centre in Italy. Brexit-related troubles have meant they've stopped taking UK orders:
UK Shipping Notice