I am British and living in London. From the article:
"London saw wild scenes of a weekend mass exodus before the start of a Christmas lockdown and travel ban sparked by a new, more infectious mutation of COVID-19."
"London saw wild scenes of a weekend mass exodus before the start of a Christmas lockdown and travel ban sparked by a new, more infectious mutation of COVID-19."
The mass travel before the Boxing Day restrictions kind of proves people were away from home, seeing family etc this spreading the virus.
For people living in London, Christmas Day was indeed a lockdown.