Simon Wood and Ernst Wit have published a paper discussing whether R<1 before the English lockdowns
Simon Wood and Ernst Wit have published a paper in PLOS1 (https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0257455) independently replicating and critiquing a major modelling study, from Neil Ferguson's Imperial College group, on the Covid-19 epidemic in England.
By moving key model parameters back to literature based values, and by allowing more freedom for data, not assumption, to determine how R changes through time, the paper shows that R most likely dropped below one before either of 2020's full lockdowns. This result is consistent with direct statistical measurements, but reverses Imperial's own headline conclusions.