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From SayNoTo0870.com forum
NGMsGhost mentioned here that it was on page 130 of the Numbering Review statement (.pdf).
A summary as follows:-0300:
UK-wide services at a geographic rate: to be used by public sector bodies and not-for-profit bodies, calls charged at up to the same rate the customer would pay to call to a Geographic Number, with calls to 03 numbers counting towards inclusive call minutes if the customer has remaining inclusive minutes to Geographic Numbers, and included in any discount structures that apply to Geographic Numbers0303:
UK-wide services at a geographic rate: calls charged at up to the same rate the customer would pay to call a Geographic Number, with calls to 03 numbers counting towards inclusive call minutes if the customer has remaining inclusive minutes to Geographic Numbers, and included in any discount structures that apply to Geographic Numbers0344/0345:
UK-wide services at a geographic rate: migrating numbers from 0844/0845, calls charged at up to the same rate the customer would pay to call a Geographic Number, with calls to 03 numbers counting towards inclusive call minutes if the customer has remaining inclusive minutes to Geographic Numbers, and included in any discount structures that apply to Geographic Numbers0370/0371:
UK-wide services at a geographic rate: migrating numbers from 0870/0871, calls charged at up to the same rate the customer would pay to call a Geographic Number, with calls to 03 numbers counting towards inclusive call minutes if the customer has remaining inclusive minutes to Geographic Numbers, and/or included in any discount structures that apply to Geographic Numbers