With a time inside, escapee will then possibly make a fresh start (4,3,5,5)
I believe the answer is:
wipe the slate clean
'make a fresh start' is the definition.
(I've seen this before)
'with a time inside escapee will then possibly' is the wordplay.
'with' says to put letters next to each other.
'time' becomes 't' (abbreviation).
'inside' means one lot of letters goes inside another.
'possibly' indicates an anagram.
'a'+'t' is 'at'.
'escapee'+'will'+'then'='escapeewillthen'
'escapeewillthen' is an anagram of 'wipethesleclean'.
'at' going into 'wipethesleclean' is 'WIPE THE SLATE CLEAN'.
(Other definitions for wipe the slate clean that I've seen before include "Forgive debt" , "as tidy roofer might?" , "Make a fresh start" .)