Fieldwork began in Wales on 29 June 2020 followed by Northern Ireland on 26 July 2020 and Scotland on 21 September 2020.
Dechreuodd gwaith maes yng Nghymru ar 29 Mehefin 2020, wedyn yng Ngogledd Iwerddon ar 26 Gorffennaf 2020 ac yn yr Alban ar 21 Medi 2020.