2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/197928We introduce a dispersionless integrable system which interpolates between the dispersionless Kadomtsev-Petviashvili equation and the hyper-CR equation. The interpolating system arises as a symmetry reduction of the anti--self--dual Einstein equations in (2, 2) signature by a conformal Killing vector whose self--dual derivative is null. It also arises as a special case of the Manakov-Santini integrable system. We discuss the corresponding Einstein--Weyl structures.11 pages. New title, some errors corrected, section 5 removed. Final version, to appear in J. Phys. AExactly Solvable and Integrable SystemsHigh Energy Physics - TheoryMathematical Physicstext