yesterday, at the Codex hackathon, i ended up solving this problem by building an MCP connector app that turns ChatGPT into Codex, sort of.
1. you get to use GPT-5.5 Pro by exposing your local dev environment to ChatGPT, so you can use 5.5 pro for planning and handover to codex to execute it
2. you get to 2x your rate limits, just like last month, because apparently ChatGPT and Codex have separate rate limits
here is the quick demo