There are two types of metric styles in IS-IS:
The range of the metric value is different for both of these styles. If there is a change in the metric-style configuration, the default-link-metric changes with it so that the new value of the default-link-metric is equal to the minimum of both the configured value and the maximum value supported for the new metric-style.
If the metric style changes from narrow metric to wide metric, no change in the value of default-link-metric occurs.
If the metric style changes from wide metric to narrow metric, and if the value of default-link-metric is greater than 63, the default-link-metric takes the value 63, as it is the maximum supported in the narrow metric.