Excess load of deliveries leading to rush (10)
I believe the answer is:
overcharge
'excess load' is the definition.
The answer and definition can be both to do with contact as well as being verbs in their base form.
Perhaps they are linked in a way I don't understand?
'deliveries leading to rush' is the wordplay.
'deliveries' becomes 'over' (I've seen this before).
'leading to' is a charade indicator (letters next to each other) (some letters go before or lead others).
'rush' becomes 'charge' (charging is a kind of rushing).
'over'+'charge'='OVERCHARGE'
'of' is the link.
Can you help me to learn more?
(Other definitions for overcharge that I've seen before include "rook" , "Demand too much money" , "Ask too much" , "Ask too high a price" , "Rip off" .)