Scope of former shelter (6)
I believe the answer is:
extent
'scope' is the definition.
(I've seen this in another clue)
'former shelter' is the wordplay.
'former' becomes 'ex' (prefix meaning former or onetime).
'shelter' becomes 'tent' (a tent is a kind of shelter).
'ex'+'tent'='EXTENT'
'of' acts as a link.
(Other definitions for extent that I've seen before include "Area covered by something" , "Area something covers" , "reach?" , "Range or scope of something" , "Length" .)