Bank overdraft fees are to undergo a major shake-up, which the UK financial regulator is calling the biggest overhaul for a generation. Banks and building societies will no longer be allowed to charge fixed daily or monthly fees for overdrafts.   In addition, there will no longer be higher fees for unplanned overdrafts than for arranged ones. The Financial Conduct Authority (FCA) said the new rules would start by April 2020.   Under the new measures, which were firs