If you move from BT Res to BT Business you will not normally be held to te remaining contract period with BT Res - it will be waived. If you are self employed you should be able to put a BT Business service through as an expense. Some accountants and HMRC are a little touchy/cautious about Residential service as an expense. You will only need to move your Infinity across and can leave the phone line on a Res service. You can then have a static IP and Next Business Day support for the service and line.
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