BumpPay asks for five pieces of operator input: role, due date, leave start date, employment start date, payroll cadence, and relevant-period earnings. From the due date it derives the qualifying week, then it frames a relevant period window for review. The earnings input is normalised into average weekly earnings using the selected payroll cadence, because monthly, fortnightly, and weekly users need the same legal logic with different operational framing.
The estimate then applies the familiar two-phase SMP structure. The first six weeks are estimated at 90 percent of average weekly earnings. The following thirty-three weeks are estimated at the lower of the standard SMP rate or 90 percent of average weekly earnings. Recovery estimates are shown separately using visible assumptions for the standard path and the small-employer relief path. None of those non-durable values are hidden in the code path for the user-facing calculator. They are visible and editable in the assumptions section.
This is also where the durability posture matters. The standard SMP rate, the Lower Earnings Limit, and employer recovery percentages can change over time. BumpPay therefore treats them as reviewed assumptions tied to source authority, not timeless constants. The logic stays stable while the values remain visible and replaceable. That is how the tool can still be useful years from now without pretending a 2026 figure will remain correct forever.