Payroll and human resources system records showing reporting lines by date, approved requisitions, performance review assignments, and organisational charts issued at known times. Where staff are contractors or shared across teams, the arrangements governing their direction matter more than a headcount figure quoted in a letter.
Do not paper over a gap
The temptation, once a conflict is found, is to issue a fresh job description that resolves it in the preferred direction. A newly written document with no history behind it carries little weight and creates a new inconsistency with everything already on file. Correct records properly, keep the superseded versions, and let counsel decide how to present the change.
An honest correction is defensible; a quiet rewrite is not. Where the honest answer is that the team has shrunk, the useful next step is to ask what the person manages instead. A role that has lost subordinates may have gained responsibility for an essential function, a budget, a supplier programme or a production line, and that is a different claim supported by different documents: approval limits, budget ownership, contracts signed, decisions recorded.
Establishing it takes the same afternoon as arguing about headcount and produces something defensible. If neither claim is supported, the finding is that the role has changed, which the business needs to know before it commits to a filing.