Maybe change in layout of linear county (10)
I believe the answer is:
lancashire
'county' is the definition.
(English county)
'maybe change in layout of linear' is the wordplay.
'maybe change' becomes 'cash'.
'in' means one lot of letters goes inside another.
'layout of' indicates an anagram.
'linear' with letters rearranged gives 'lanire'.
'cash' placed inside 'lanire' is 'LANCASHIRE'.
(Other definitions for lancashire that I've seen before include "Stew from the Northwest" , "it includes Leyland" , "Part of country" , "North-Western county" , "Crumbly white cheese" .)