Payroll registers, tax slips, records of employment and dated assignment letters. A summary letter from the employer supports those records but does not replace any of them.
Assemble the year month by month
The payroll register shows continuity and full-time hours; tax slips confirm who paid; a record of employment marks any interruption and its stated reason. Where the manager worked away from the plant, produce the assignment letter, the project correspondence and the invoices showing the customer was billed by the employer rather than employing him directly. Parental leave, medical leave or a lay-off should be identified, dated and explained rather than smoothed over, because the three-year look-back may still contain a complete qualifying year on either side of it. Add the job descriptions that were in force during that year and an organizational chart as it stood then, not as it stands today. If the company reorganized during the period, include the documents showing that the manager's employer remained a qualifying organization throughout the whole of it.
Hypothetical example: a lithium-battery recycling business changed payroll providers during its director's overseas employment. The first review should reconcile pay slips, tax records, employment agreements, leave records, and the provider-transition notice into one month-by-month timeline. The employer's registry filings settle corporate identity, while payroll and work records settle the employment period. Obtain missing months before drafting the support letter. The ordinary error is relying on an annual earnings summary that proves pay but not continuous, qualifying employment or the actual entity that employed the manager.