> Aren't they all billing at discount?

Microsoft just announced the availability of OpenAI GPT-5.5, which they are charging 30x for it. In contrast, they charge 7.5x for Claude Opus 4.6 and 1x for OpenAI GPT-5.4

Check out the token-based pricing, and compare GPT-5.5 with all other models.

https://docs.github.com/en/copilot/reference/copilot-billing...