Sonnet 5 Medium and GPT 5.5 Medium for coding. I drop down to a Mini model for file-based tasks. Codex keeps trying to revert me back to 5.6 but 5.6 seems to

Sonnet 5 Medium and GPT 5.5 Medium for coding. I drop down to a Mini model for file-based tasks. Codex keeps trying to revert me back to 5.6 but 5.6 seems to use too many tokens to do the same or slightly inferior job. I am only on multiple $20 plans.