The rule that pays it, running.
Léa is hired on 4 May with a three-month trial period. The rule reads both from her contract and writes down 4 August. On 4 August it asks the employee file one question, is she still here, and on yes it creates a payroll input of €500.00 for Karim on the August run. On no, it closes the referral as not earned and says why. Nobody keeps the date in a diary and nobody tells payroll. The rule is one you can read and change: the trigger, the check, the amount, the run it lands on; two parts, a cap or a different amount per job are edits, not requests. The amounts here are examples; what the payslip withholds from a referral bonus follows the rules your payroll applies ⟨to confirm⟩.