The latest update to the online Who's Who./Who Was Who shows that Sir Jan Hew Dalrymple-White, 3rd Bt., died on 15th October 2025 aged 74. He succeeded his father, Sir Henry Arthur Dalrymple-White, 2nd Bt., in 2006, although never proved his title on the Official Roll of the Baronetage..
Who Was Who records a son from the second marriage but no heir is listed, and from my research thus far it seems the child was born before the marriage. I do not know if there are other candidates for the title. I can find no other online references to his passing.