The Payroll Cutover Date
A retail chain of 22 stores is replacing its payroll system. The current system is end-of-life and the vendor will stop supporting it in 10 weeks. The new system has passed unit testing but integration testing with the time-clock hardware in stores has not started, and two stores use older clocks the vendor has not certified. Training for 60 store managers is scheduled for week 8. The project sponsor wants to cut over in week 9 to avoid paying for an unsupported system, and proposes cutting over all 22 stores at once "to get it done". The payroll manager notes that an error in a pay run affects every employee and is highly visible.
1. Evaluate the sponsor's proposal and recommend a cutover approach.
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The sponsor's date is driven by the support deadline, which is real, but a single big-bang cutover in week 9 is high risk because the two most failure-prone activities, integration testing with store clocks and manager training, are both incomplete. Payroll errors affect every employee, are highly visible, and are hard to reverse once money has been paid, so the cost of a failed cutover exceeds the cost of a short support extension.
The recommendation should separate the deadline from the cutover method. First, ask the current vendor for a short paid support extension to remove the artificial urgency, and confirm the cost. Second, complete integration testing, prioritising the two uncertified clocks: either certify or replace them, or run those stores on a documented manual process for the first cycles. Third, run a parallel or pilot cutover with a small group of stores for at least one full pay cycle, comparing outputs against the old system before rolling out to the remaining stores. Training must precede the pilot, not the full rollout.
A phased cutover with a verified pilot converts an all-or-nothing gamble into a controlled transition, and the support extension buys the time to do it. If no extension is possible, the fallback is to cut over in waves with the lowest-risk stores first and a tested rollback plan for each wave.
2. Describe the acceptance criteria and rollback conditions the project should define before any store goes live.
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Acceptance criteria should be measurable and tied to pay accuracy and operational readiness. Examples: a full parallel pay run for the pilot stores matches the old system to the cent, with every variance explained; all time-clock integrations pass end-to-end tests, including the two older clocks or their documented workaround; all 60 managers have completed training and can process a pay cycle unaided; and support arrangements are in place for the first two live pay cycles.
Rollback conditions should be agreed in advance and stated as triggers, not left to judgement in the moment: for example, if the parallel run shows unexplained variances above an agreed threshold, if integration testing fails for a store's clocks, or if the pilot pay run cannot be completed by the deadline. The rollback plan must say how to revert to the old system or manual process, who authorises it, and how employee pay is protected during the revert. Defining these before go-live is what makes the phased approach meaningful, because a pilot with no agreed failure criteria is just a smaller big bang.