Its not difficult to understand why/who - With over 106,000 fatalities, according to Johns Hopkins University data, Britain has seen the deadliest coronavirus outbreak in Europe

Most certainly during such virus outbreak, there will be other variations of virus(far deadlier), government would release as needed. South Africa(as I explained you time and again for several year on row) was/is number 1 target of Buckingham palace abroad.

From https://www.voanews.com/covid-19-pandemic/britain-identifies-105-cases-south-african-covid-19-variant and https://www.voanews.com/covid-19-pandemic/britain-identifies-105-cases-south-african-covid-19-variant