1. Jurisdiction of courts to vary trusts.
— (1) Where property, whether real or personal, is held on trusts arising, whether before or after the passing of this Act, under any will, settlement or other disposition, the court may if it thinks fit by order approve on behalf of—
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(b) any person (whether ascertained or not) who may become entitled, directly or indirectly, to an interest under the trusts as being at a future date or on the happening of a future event a person of any specified description or a member of any specified class of persons, so however that this paragraph shall not include any person who would be of that description, or a member of that class, as the case may be, if the said date had fallen or the said event had happened at the date of the application to the court