Although it seems very common practice amongst conservation organisations to fully review management plans every five years, there is a strong argument for limiting any changes to just those sections that absolutely need it. Indeed, it seems theoretically possible to separate plans into descriptions and evaluations, which remain almost static for long periods of time, and objectives and action plans which are reviewed at regular intervals.
The site description may not need any changes, or just minimal updating.
The site evaluation and objectives are likely to need a check, but this may not lead to any revision.
Unless the vision has proved to be misguided, it’s good practice to leave it as it is.
Objectives may require some revision based on a review of the successes and failures of the management undertaken in the previous years.
Clearly, the action plan will need revision, although resource requirements can be refined if records have been kept of financial and time inputs to achieve the previous version of the plan.