The 'manage by stages' principle in PRINCE2 dictates that the end of each stage provides a control point at which the project board can review progress, reassess project viability, and decide on the next steps. This approach allows for regular monitoring and decision-making, ensuring that the project remains aligned with its objectives and within its tolerances.References: PRINCE2 7 Foundation guide on the 'manage by stages' principle.

Achieving the principle of 'ensuring continued business justification' involves confirming that the project remains desirable, viable, and achievable throughout its lifecycle. Adapting PRINCE2 to the project's scale of investment and the chosen delivery approach helps maintain its alignment with business justification, ensuring that the project's scale, complexity, importance, capability, and risk are proportionate to the project's objectives and environment.References: PRINCE2 7 Foundation handbook and documents on the principles of PRINCE2.

During the 'Maintain' step of the 'business case management' technique in PRINCE2, the project manager assesses the ongoing viability of the project against the business case, including whether the outcomes are likely to deliver the expected performance improvements post-project. This is a continuous process that ensures the project remains aligned with business needs and expected benefits throughout its lifecycle.References: PRINCE2 7 Foundation documentation on business case management.

In PRINCE2, a Team Plan is a type of plan that might only be produced for very large or complex projects. It is typically more detailed and is specifically designed to manage a segment of the project within a certain team or group. This plan provides detailed guidance on the delivery of the products assigned to the team within the constraints set by the Stage Plan.References: (PRINCE2 7 Foundation Handbook, AXELOS)

The expected success level for benefits, time, cost, quality, scope, sustainability, and risk in a project should be set by the project baseline. The baseline establishes the initial scope of what the project is expected to deliver, including standards and targets against which project performance can be measured.References:
PRINCE2 7 Foundation sources on project planning and control.