Recommend making an appointment about case shortly (8)
I believe the answer is:
advocate
'recommend' is the definition.
(I know that recommend can be written as advocate)
'an appointment about case shortly' is the wordplay.
'an' becomes 'a'.
'appointment' becomes 'date' (synonyms).
'about' is an insertion indicator.
'case shortly' becomes 'voc' (abbreviation for the vocative case in grammar).
'date' placed around 'voc' is 'dvocate'.
'a'+'dvocate'='ADVOCATE'
'making' is the link.
(Other definitions for advocate that I've seen before include "Public supporter" , "Person who pleads on behalf of another, like barrister" , "Recommend - person acting on another's behalf" , "Champion" , "barman" .)