The original post was amended on December 30 to clarify that genomic data was only available for English local authorities. In the initial version of the report, data from 28 viral genomes (out of a total of 44,445) mapped to 2 Welsh authorities was erroneously included. These were subsequently removed and the analysis rerun. All numbers and figures have been updated to the new analysis version in addition to textual clarifications. The conclusions remain unchanged.