Previously having run it hot for her to get into (8)
I believe the answer is:
hitherto
'previously' is the definition.
(thesaurus)
'run it hot for her to get into' is the wordplay.
'run' indicates anagramming the letters (I've seen this in other clues).
'for' is a charade indicator (letters next to each other).
'to get into' is an insertion indicator.
'it'+'hot'='ithot'
'ithot' is an anagram of 'hitto'.
'hitto' enclosing 'her' is 'HITHERTO'.
'having' is the link.
(Other definitions for hitherto that I've seen before include "So far" , "Previously" , "Up till now" , "Up to this time" , "Up to this point" .)