When a squadron was issued "new Models", EVERYONE got them. No pilot had enough pull to "hang on" to an older model as this would cause repair/maintenance issues. When all P-47 units were issued the "D" model, all the Razorbacks were gone. As to the Liberators,they were the chosen plane for sea rescue account of their longer range. Although some Forts were used, they were far outnumbered by the Liberators.