There’s been a discussion on Mumsnet recently on this subject. There didn’t seem to be any panic, but apparently quite a few people are buying in a few extra packs of nappies, tinned stuff, etc, now just in case there are any temporary supply issues or panic buying when Brexit happens. I suspect there will be panic buying - a couple of snow days can cause that - so it seems sensible. Doing it now, moderately and gradually, will help avoid shortages rather than cause them. I might buy an extra multipack of beans this week, just in case. 