BBC initially advertising free? (6)
I believe the answer is:
auntie
'bbc' is the definition.
(nickname for the BBC)
'initially advertising free?' is the wordplay.
'initially' indicates taking the first letters.
'free?' becomes 'untie' (I've seen this in another clue).
The first letter of 'advertising' is 'a'.
'a'+'untie'='AUNTIE'
(Other definitions for auntie that I've seen before include "Family relative" , "Unite a strange relative" , "The Beeb" , "Female relative" , "Female relation" .)