What happens to copier profits when a signal switches their performance fee?

If you copy a signal which later changes their performance fee, the new fee will only be charged to new copiers or to existing copiers if they decide to  re-copy.  

For example, if the fee is increased from 30% to 50%, existing copiers will remain on 30% unless they stop copying the signal and then start copying again, in which case the new fee will apply.