The referral payment is for past referrals, and stops when the person referred leaves Plusnet. If they choose to stay they are more or less satisfied with it, and the payment is justified.
I too still receive referral payments, but stopped recommending them long ago.
Similarly, in a very different field, many years ago I made several investments through Chase de Vere after they made suggestions. They received an annual commission on some of those until I sold the investments. I doubt very much if they were still making the same recommendations throughout the period I had the relevant holdings.
Kindness isn't going to cure the world of all its awfulness but it's a good place to begin. Daisy Ridley.
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