I've had the exact same experience. Email received saying "Because of these changes you have the right to end your tariff without having to pay an Early Termination Charge".
Spoke to an online advisor who said apparently I am not affected so the question remains who is?
Agin I ask what are the circumstances that apply to allow ending of contract early?
is it a case that o2 have changed the terms and conditions of the original contract I signed up to in Feb 20 by moving me to their new pay monthly mobile agreement as described in email?
Only effected by the 3.9% if refresh contract was taken after march 2021.
Contracts prior to that are just the usual annual RPI increase.
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