m_pavlov/Thinkstock At 11 p.m. Dec. 31, Brexit gets real, with departure bringing a host of new regulations and customs paperwork. Bloomberg | Dec 31, 2020 By Lizzy Burden and Richard Weiss On the day the U.K. makes its final break with the European Union, the ports are clear of truck backups, goods are moving smoothly and grocery-store shelves are well stocked. Even so, U.K. businesses that rely on some 1.2 billion pounds ($1.6 billion) worth of products crossing the border each day are taking no chances. At 11 p.m. Thursday, Brexit gets real. Companies were already stockpiling and exploring alternatives to the crowded truck-ferry route across the English Channel when France unexpectedly closed its border for two days last week, citing a fast-moving Covid-19 outbreak in the U.K. The disruption produced miles-long backups at the Port of Dover -- a warning shot for potential chaos as the Brexit transition period ends.