Subsequent change, with delayed start (5)
I believe the answer is:
later
'subsequent' is the definition.
(similar in meaning)
'change with delayed start' is the wordplay.
'change with' becomes 'r' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'delayed' becomes 'late' (I've seen this before).
'start' is a charade indicator (letters next to each other).
'r' put after 'late' is 'LATER'.
Can you help me to learn more?
(Other definitions for later that I've seen before include "at a future date" , "When to see you?" , "there's more behind" , "Following" , "At a time in the future" .)