Right, what remains in use, not for the first time? (6)
I believe the answer is:
rehash
'use not for the first time?' is the definition.
I can't tell whether this definition defines the answer.
'right what remains' is the wordplay.
'right' becomes 'r' (abbreviation).
'what' becomes 'eh' (sound used to ask 'what?' or 'pardon?').
'remains' becomes 'ash' (remains of a fire).
'r'+'eh'+'ash'='REHASH'
'in' is the link.
Can you help me to learn more?
(Other definitions for rehash that I've seen before include "Rework old material" , "Makeover" , "That's nothing really new" , "makeshift changes?" , "Same material, different mix" .)