This is a configurable timer. After the failover, on the new AMM, the route and neighbor table entries are marked as stale in the FIB. As routing protocols begin to re-add routes, this stale flag will be reset. When this timer expires, all route and neighbor table entries still marked stale [not yet re-added] will be removed. A value of 0 means that no layer 3 hitless behavior is desired, and in this configuration, upon failover all FIB entries are flushed and corresponding hardware entries are removed. A default value of 5 minutes is chosen with the assumption that the routing protocols can finish re-adding the routes to the equivalent state within this time.