BREXIT: 11pm (GMT) on 31 December 2020 (‘IP completion day’) marked the end of the Brexit transition/implementation period entered into following the UK’s withdrawal from the EU. Following IP completion day, key transitional arrangements come to an end and significant changes begin to take effect across the UK’s legal regime. This document contains guidance on subjects impacted by these changes. Before continuing your research, see: Brexit and financial services: materials on the post-Brexit UK/EU regulatory regime. What requirements must a mortgage lender consider before trying to enforce its power, to avoid challenges by the borrower? There are two sets of rules and regulations that the lender must comply with in order to be able to rely on its unilateral power without challenge: • the rules in the FCA Handbook: the Principles for Businesses, and the Mortgage Conduct of Business Sourcebook (MCOB), and • the Unfair Terms in Consumer Contracts Regulations (UTCCR 1999), SI 1999/2083 There is considerable overlap