BUT if, using FreeBMD, you specify a surname of EVILL and the county as Denbighshire, there are only two registrations. However, if you specify the same surname and choose Derbyshire there are a large number - the majority in Chesterfield RD and Bolsover is located within that RD.
I was drawing attention to the (very often) confusion of Denbighshire and Derbyshire in transcriptions rather than this one specifically.
Over the years, I've seen a lot of transcription mistakes while looking for kin in Denbighshire.
Gadget
add -e.g. from original post:
Does anyone know if the registration district for Derbighshire changed to Stoke on Trent Staffordshire sometime after 1939? I have the Evill family living in Bolsover Derbighshire with all registrations in Derbighshire up to 1939