Mobile numbers have never used the 070 range.
Since the Big Number Change in April 2000 the 070 range has been used only for Personal Numbers charged at a premium rate. Personal Numbers were first allocated with 070 prefixes in 1995. At that time, the rest of the 07 range was almost empty, with geographic 07xx prefixes recently migrated to 017xx ranges.
Mobile numbers have never had 070 prefixes, neither before or after the Big Number Change.
Before the Big Number Change existing mobile numbers were spread through the 03xx, 04xx, 05xx, 08xx and 09xx ranges. After about 1997 most new mobile numbers were issued within the 077xx, 078xx and 079xx ranges. Immediately after the Big Number Change all mobile numbers were confined to use only the 077xx, 078xx and 079xx ranges. Over the years, additional 075xx, 074xx and 073xx number ranges have come into use for mobile phones.
Until 1995, area code 0706 was assigned to geographic numbers in Rochdale. This area code changed to 01706 in 1995.