Make the immediate workload visible
Before rewriting the job advertisement, identify what will need an owner during the transition. Look at scheduled meetings, upcoming deadlines, unresolved committee matters, active projects and correspondence waiting for a response. Ask the departing manager to explain the exceptions that are not obvious from the records.
A practical handover should distinguish urgent decisions from routine follow-up. A long task list with no priorities leaves the next person to reconstruct the situation under pressure.
Decide what your existing team can absorb
Talk to the people who would be taking on extra work. Check their meeting schedules and current demands before distributing another portfolio. Make the temporary allocation specific, with a person responsible for each area and a date to review it.
If your experienced managers can make the key decisions but lack time for coordination and administration, targeted support may be more useful than trying to replace every part of the departing role at once.
Separate cover from the permanent appointment
The person who can help through a transition is not necessarily the person you want in the role long term. A temporary deployment can give you another option while the permanent recruitment process continues. It still needs a proper brief and a workable handover.
Describe the systems, level of responsibility, expected hours and likely duration. Be clear about what is known and what may change. We can then discuss suitable availability and proposed arrangements without pretending every urgent request has an immediate solution.
Keep the team and clients informed
Explain the interim contact arrangements and make sure urgent matters have an escalation path. Internally, agree who can approve decisions, provide system access and answer questions for the incoming person. Access should be appropriate to the work and removed when the assignment finishes.
Use the transition to learn what the permanent role needs. If the workload has changed, recruiting to the old job description may recreate the same pressure. Tell us about the immediate gap and the longer-term objective so we can consider both.