Been a member for some years now and tend to visit NT sites about this time of year (September) when we explore somewhere in the UK. Now apparently one has to book in advance else you cannot visit on spec. Pray tell me what is the point of being a member? Utterly impossible to contact any of the sites we wished to visit only to be referred to some hopeless call waiting system! This has annoyed me intensely to the point where I have now cancelled my membership. Indeed as noted by some others, clearly the NT shows nothing but contempt for existing members!