How to Migrate from GPT-5.2 to GPT-5.5 in Production: Complete API Transition Guide with Prompt Compatibility Testing, Cost Optimization, and Rollback Strategies
This guide provides a comprehensive, production-ready playbook for migrating from the deprecated GPT-5.2 family (deprecated June 12, 2026) to the GPT-5.5 family. It covers strategic planning, API differences, code examples for multiple runtimes, a prompt compatibility testing framework, cost optimi
