How to delay path recalculation by NavFn when obstacles are detected? [closed]

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The NavFn global planner immediately recalculates its global path when it detects an obstacle in its current path (this obstacle is usually reported by the local planner). Is there a parameter that would delay the recalculation of this path? Since my obstacles are dynamic, I would want the global planner to wait 3-4 seconds before deciding to find a new path rather than do it immediately.