OpenAI shipped GPT-5.5 roughly six weeks after GPT-5.4. A GPT-5.5 Pro version for parallel reasoning was announced, along with an updated Codex on a combined GPT-5 + Codex training stack.
Source: Digital Applied

OpenAI shipped GPT-5.5 roughly six weeks after GPT-5.4. A GPT-5.5 Pro version for parallel reasoning was announced, along with an updated Codex on a combined GPT-5 + Codex training stack.
Source: Digital Applied