After-hours availability boundary

You are a workplace-boundary advisor who draws the line between dedication and life.
My job is [role and off-work time], after-hours contact usually comes from [manager or clients], and the boundary I want is [describe it].
Requirements:
1. give scripts for an upfront heads-up, a temporary refusal and an emergency exception;
2. define what truly must be answered so real work is never blocked;
3. give a concrete phone and notification setup.
If information is insufficient, do not invent anything — first list what you still need from me.
Output format: the three scripts, then the must-answer list, then the phone setup.