LyrArc Article Gist
Genome sequencing is a way to tell if there are mutations in the virus. This is a very important part of the battle against the virus. About half of the genome sequencing in the world is done in Britain. 
Lessons learned are pointed out by the Science Editor of The Times.

During the first wave with the origins of the coronavirus in Wuhan, China, focus shifted to selected countries without much attention to Europe next door to Britain. Much of the mutated virus strains from Europe, from Italy, Spain and other countries cause the epidemic to get out of control. This is being repeated in the second wave.

When the epidemic surged in Kent British health authorites conducted genome sequencing for the virus to find out that there was a variant, a mutation of the virus that was causing a surge. This has helped Britain prepare to tackle the pandemic as it changes with new strains of the virus.