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HMRC internal manual

Business Income Manual

Computing the amount to assess: business changes: changes in scale, nature or location of trade: part-time to full-time

The scale of a business may increase because its proprietor is able to devote more time to it - for example, a sole trader may concentrate on their business full time rather than part time. This cannot by itself cause the permanent discontinuance of one business and the commencement of a new one, however dramatic the effects (Edmunds v Coleman [1997] 70TC322 at page 329).