A little detail starts to emerge. NERVTAG (science committee minutes) have been published.
Estimated increase in R from new variant 0.39-0.93. By comparison, closing all schools is estimated to reduce R by 0.4. I'm still sceptical it's really that bad, R estimates for this are very difficult, but that's really just personal speculation.
Terrible case numbers today too, 35,000
It's doubling every 6 days under tier 3. That's ~100x increase by end Jan. I think we're now into "full national lock down until vulnerable are vaccinated" territory, unless those estimates are significantly out.
Doubtless that won't be announced until Johnson has repeatedly promised not to, insulted anyone who suggests it and then waited until the absolute last moment.
View: https://mobile.twitter.com/Smyth_Chris/status/1340667844741230594