On June 7th, 2019 the UK government announced that they were moving the Early May Bank Holiday in 2020 to mark the 75th anniversary of VE Day. The holiday will move from Monday 4th May to Friday 8th May for 2020 only.
Unfortunately, many calendar publishers had already printed their 2020 calendars by the time of the announcement. As a result, please be aware that some 2020 calendars may have the Early May Bank Holiday marked as the incorrect Monday 4th May. This will be the only date in your calendar affected by this change.
For further information about the change, please read this BBC article on the government announcement.