BGP doesn't really cache routes, though you can configure routers to hold a route for some time if a peer times out, but this is only used in special cases and

BGP doesn't really cache routes, though you can configure routers to hold a route for some time if a peer times out, but this is only used in special cases and usually not something you would want your router to do with routes to other networks. If a router gets a withdrawal for a route it will remove the route from the table without waiting. This is a feature and important part of how BGP acts in case of problems and how it can self heal quickly, there's no point in caching a route when that path is not working anymore and usually there's a backup path.