'Plan Y' (ii) was an Allied plan, later redesignated as 'Plan O', for the accelerated development of the forces in northern France after 'Overlord', envisaging 27 divisions by D+120 and 34 divisions by D+150 (mid-1944).
Basic overview
Date: 30 November 1943
Scope: Major
Nature: Land, Reinforcement/build-up
Status: Implemented