Too heavy concerning reported delay (10)
I believe the answer is:
overweight
'too heavy' is the definition.
(I've seen this before)
'concerning reported delay' is the wordplay.
'concerning' becomes 'over' (both can mean relating to).
'reported' shows a homophone (sound like).
'delay' becomes 'wait' (synonyms).
'wait' is a homophone of 'weight'.
'over'+'weight'='OVERWEIGHT'
(Other definitions for overweight that I've seen before include "Obese" , "Too heavy" , "Big" , "Carrying a lot of stones" , "stout" .)