A large fraction of the design changes are mandatory, without even considering the local regulator, due to the sheer geographical difference between sites. Hink

A large fraction of the design changes are mandatory, without even considering the local regulator, due to the sheer geographical difference between sites. Hinkley Point: tunnels (AFAIK: 9 km-long), a seawall... Even climate is a factor. There will always be a local regulator, and the push to adopt common requirements (even enforced by the pertinent UN agency, the IAEA) is limited by the need to double-check (keeping many distinct eyes on the subject in order), its own tropisms and also will/need to justify itself by avoiding to simply copy-paste. All this will probably prove to be quite an ordeal for any "let's build thanks to components sent by a factory" approach (SMRs...).