Bishop departs behind schedule in a joyful manner (8)
I believe the answer is:
elatedly
'bishop departs behind schedule' is the definition.
I can't judge whether this definition defines the answer.
'joyful manner' is the wordplay.
'joyful' becomes 'elated' (synonyms).
'manner' becomes 'ly' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'elated'+'ly'='ELATEDLY'
'in a' is the link.
Can you help me to learn more?
(Other definitions for elatedly that I've seen before include "Joyfully" , "showing great emotion" , "Happily" , "high spirits" .)