With repeated vendor delays and no option to replace the vendor, the project manager must actively manage the supplier relationship and develop a realistic recovery plan. Reaching out to the vendor to create a plan (C) is the most effective action: confirm root causes, agree on an achievable delivery schedule, identify acceleration options (expedite shipping, partial deliveries, priority allocation, additional shifts), and define monitoring and escalation checkpoints. This aligns with procurement management and issue management: collaborate first to restore performance while protecting the 90-day constraint. Threatening penalties (A) may be part of the contract strategy, but leading with penalties can damage collaboration and may not produce a practical recovery plan. Waiting to use contingency funds (B) is reactive and risks missing the hard deadline. Reviewing lessons learned (D) is helpful, but it does not directly address the immediate supplier performance problem. A vendor recovery plan with clear commitments, accountability, and frequent tracking best supports schedule control under tight constraints.

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