@afameen If you are transferring your phone number to BT that will cease your Plusnet service so you shouldn't need to tell Plusnet. Just make sure there are no early termination fees on your final bill which will not be produced until about 3 weeks after you have left.
I've put a marker on your account for us to waive termination fees when we generate your final bill, providing your account's cancelled within the next 30 days. If you need longer let me know, or if BT don't takeover your existing phone line and just install FTTP without a phone number, I'd recommend calling us back so we can cancel your account manually.
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