How to Negotiate Scope, Title, and Flexibility —
Not Just Salary
To negotiate beyond salary: name the work that's already expanded, then negotiate the architecture around it: title, scope, decision rights, flexibility, a review date as a package. Use the move "the work has moved to X, the terms still reflect Y, I'd like to change Z."
If salary can't move, ask which other terms can. When the work is permanently called "growth" but no term ever changes, it's a convertibility problem, not a negotiation one.
Terms are the architecture around the job you actually do.
More responsibility without more authority is not development. It is exposure.
The role already changed. The only open question is whether you keep letting the company set the terms by itself, or start naming them too.