The suppression model adopted by *only every other country on the planet* would almost certainly mean a transition extension.
The way I see it the "herd immunity" wheeze means a short sharp economic crash followed by a sharp recovery and the only downside (trivial to Tory thinking) a lot of dead people. But the WHO strategy is 18 months to 2 years slowdown while a vaccine is developed.
How many weeks (and lives) did this cost?