@biffvernon thanks for sharing, I've read Guy's book - it is brilliant.

Based on the prevalence of indicator species, there are potential rainforest areas further east than the currently published studies. I know Guy's project is a work in progress (a brilliant one at that), so there's clearly more to do.

This map uses crowdsourcing to identify potential locations google.com/maps/d/u/0/viewer?h

There are some fairly extensive liverwort studies in woodland in Derbyshire, too.