I was told the last week of three people in customer services the exact same thing and my girlfriend works on a cruise ship that travels around the world. She uses the 4:1 and was told of CS that if she changes she will lose the 4:1 offer. Today she phoned up again to request a microsime transfer and soemone called Mark (i also have CS details) said that because she pays £35 a month there is some international tariff already on her account which is free because of the amount she pays. This means she can change to any iphone tariff (aslong as she is £35 min) and keep the 4:1.
I mentioned to him the fact that other CS people said that the 4:1 no longest exists on new tariffs but he said this is not true and has been selling them with 4:1 for years now!
I called again later tonight but after 36 mins waiting in a queue i gave up
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