Copper overwhelmed by demand reviewed schedule for summer (10)
I believe the answer is:
calculator
'summer' is the definition.
(something which does sums)
'copper overwhelmed by demand reviewed schedule' is the wordplay.
'copper' becomes 'Cu' (chemical symbol).
'overwhelmed by' indicates putting letters inside (inserted letters get absorbed or overwhelmed).
'demand' becomes 'call' (call is a kind of demand).
'reviewed schedule' becomes 'ator' (I can't justify this - if you can you should believe this answer much more).
'cu' inserted within 'call' is 'calcul'.
'calcul'+'ator'='CALCULATOR'
'for' is the link.
Can you help me to learn more?
(Other definitions for calculator that I've seen before include "this should provide some answers" , "Ready reckoner" , "Sum-doer's aid" , "See 12" , "Adding machine" .)