Payroll Cutover at the Holiday Freeze
A 5,000-employee manufacturer is moving payroll from an on-prem system to a SaaS provider. Cutover is the last weekend of November; the first pay run is December 1. An October parallel run matched 99.2% of records. The 0.8% mismatches are mostly shift differentials and one union local's retro pay. The vendor's change freeze begins December 15. The payroll manager wants to postpone to January. The CFO says the legacy license expires December 31 and the vendor will not extend. Testing found a defect in overtime for employees who cross midnight; the vendor's fix is scheduled for November 27, two days before cutover. The rollback plan requires the legacy system to remain available for 10 business days, but infrastructure has begun decommissioning one of two legacy servers.
1. Assess delivery readiness. Recommend go, no-go, or conditional go, and justify with specific criteria.
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Assessment: not ready for an unconditional go. Recommend a conditional no-go until evidence closes the critical gaps.
Readiness criteria and current status
- Defect closure: the cross-midnight overtime defect is systemic and directly affects pay. A fix scheduled two days before cutover leaves no time for regression testing, parallel validation, and payroll sign-off. This is a blocking condition.
- Data reconciliation: 99.2% sounds high, but 0.8% of 5,000 employees is about 40 people, including union retro pay. Payroll errors are not acceptable at that rate without manual resolution. Require 100% reconciliation of the union local and a documented exception process for the rest.
- Rollback capability: the rollback plan requires 10 business days of legacy availability, but one of two legacy servers is being decommissioned. The plan is not executable. Restore capacity or renegotiate the rollback approach before cutover.
- Change freeze: the December 15 vendor freeze means any post-go-live defect may not be fixed during the first critical pay cycles. Require a freeze exception or a support commitment.
Recommendation: delay the cutover until the defect is fixed and regression-tested, reconciliation is complete for the union population, and rollback is restored. If the business insists on the November date, require a written risk acceptance, a manual payroll contingency, and an off-cycle payment plan.
Reasoning: payroll is a high-consequence process with legal and employee-trust impact. A 99.2% match rate and a last-minute fix are not sufficient evidence of delivery readiness.
2. Identify the top delivery risks and propose mitigations, including the legacy server decommissioning and the December 15 freeze.
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Top risks and mitigations
- Overtime defect not validated. Mitigation: freeze scope, require vendor fix by a date that allows at least five business days of regression and parallel testing; add targeted test cases for cross-midnight shifts; do not accept 'fix delivered' as 'fix verified.'
- Loss of rollback capability. Mitigation: halt decommissioning immediately; restore the second legacy server or provision equivalent capacity; test the rollback procedure end to end; define trigger criteria and decision authority.
- Vendor change freeze. Mitigation: negotiate a named support team and an exception path for severity-one payroll defects; document response times; consider moving cutover earlier or delaying until after the freeze.
- Union retro pay and shift differentials. Mitigation: assign a dedicated reconciliation team; obtain union validation; run a manual shadow payroll for the affected population; prepare off-cycle payment capability.
- Compressed timeline. Mitigation: use a stage gate with daily readiness checks; prepare a contingency budget; communicate a fallback date.
Reasoning: the largest risk is not the SaaS product; it is the loss of recovery options and the absence of time to validate a known pay-affecting defect. Mitigations should restore options before optimizing the date.
3. What decision-making and communication approach would you use with the CFO, payroll manager, and vendor?
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Decision approach
- Use a stage-gate review with objective evidence: defect verified, reconciliation signed off, rollback tested, vendor support confirmed, and payroll manager acceptance. Each gate has an owner and a pass/fail criterion.
- Present options, not just a recommendation: go on November 30 with risk acceptance; delay to January with a legacy extension or bridge contract; or phased cutover by employee group. For each, state cost, payroll risk, and reversibility.
- Escalate the legacy license and server decommissioning as a joint business and IT decision, not a project-team issue. The CFO must choose whether to fund an extension or accept payroll risk.
Communication
- Give the CFO a one-page risk summary with the 0.8% population, the overtime defect, and the rollback gap. Avoid presenting 99.2% without context.
- Agree with the vendor on escalation names, response times, and a freeze exception. Put it in writing.
- Prepare employee and manager communications for either outcome, including off-cycle payment contingencies.
Reasoning: the decision is a risk-acceptance decision, not a technical one. Clear options and written acceptance protect the organization and make accountability explicit.