I have the impression that the UK government uses the R for propaganda.The R number is not at all real.
Thay may explain why they avoid calling it R0.
It's widely accepted that R0 represents how many people an average person with a virus infects. The infection cycle is about a 5 days-10 days, so it can be approximate to about a week for which we have daily reports.
Today's report for example says this:
Cases
People tested positive
Latest data provided on 18 January 2021
---------------------------
Daily
37,535
Last 7 days
314,980
-89,975 (-22.2%)
Clearly, R0 is 22.2% less than 1.
UK government insists on using a range because of geographical differences in infectivity to muddy the water.
Claiming that 'R' is greater than 1 justifies strong restrictions, less than 1 justifies priotising the economy while claiming they follow the science.
I would like the government leaves the responsibility of publishing 'R' to the ONS.