Did a mobile number exist in 2003?



I have a document dated about 10 years ago that contains a mobile number.

I need to prove whether the date on the document is genuine or not.

Is there any way to check when a specific mobile number first came into use? Would a mobile company play ball in providing that information.

The first five digits are 07768
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Les Desser
(The Reply-to address IS valid)
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