Barclays Wealth Trustees – English Court of Appeal indicates that the determination of whether there is a single trust should accord with how a trust lawyer would view the matter
Henderson LJ rejected a submission on behalf of HMRC that a separate settlement (i.e., trust) was created whenever further property was contributed to be held by the trustee of a previously-settled trust. He stated that his single-trust view was “how a trust lawyer or practitioner would view the matter,” and also was consistent with the statutory definition (in the Inheritance Tax Act 1984) of “settlement,” which referred to “any disposition or dispositions of property … whereby the property is for the time being … held in trust….”
Neal Armstrong. Summary of Barclays Wealth Trustees (Jersey) Limited v. Commissioners for Her Majesty's Revenue and Customs,  EWCA Civ 1512 under s. 104(1) and Statutory Interpretation – Interpretation/Definition Provisions.