The text messages aren't stored by Vodafone's message centre unless the recipient's phone is switched off. Even then they are only store for a relatively short period of time, usually 72 hours or so. Once that time has passed, the messages are deleted. They are also deleted from the servers once they have been delivered, so I am not sure where you get the idea that the police can request this info - as far as I am aware the info doesn't actually exist other than the log of number 1 sent a text to number 2 at 13:08:42 on 23/10/2013
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