With Orange the period is six months.
The "security reasons" tend to be there to allow them to disconnect the number from the network. Covered in the small print, Numbers that have'nt been used for a while go into quarantine for three years, minimum. My old Cellnet number from 2000 is still in quarantine & the company,now owned by Vodafone, will not release it. So it can't be "recycled".
A mate of mine got a new mobile phone and number.
The old number was back in use within 2 weeks !
It went to a minicab driver who, as my mate had forgotten to tell people that he had changed number (even his parents!), the minicab driver was continually getting texts and confused calls from people wanting to know why he had 'stolen' the phone
Same applies to my old land line number, I went off travelling, the flatmates did not pay the phone bill, phone was cut off, and reallocated within about 10 days to a man who made it ex directory but must have been getting calls for years to come as the number was printed on thousands of business cards, was listed in adverts and was the contact number on the back of a Top 10 best selling record of the day.
When I got back they would not give me my number back despite all the hassle it was causing the new owner.
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