Get on board, as there's no end to the refunds (4)
I believe the answer is:
surf
'get' is the definition.
The answer and definition can be both related to change as well as being verbs in their base form.
Maybe you can see an association between them that I don't see?
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for surf that I've seen before include "Shore foam" , "Seaside froth" , "Ride waves - browse net" , "Ride a wave" , "Foam from breakers" .)