It depends on the availability of the seats on the next bus. Generally, there is no criterion of automatically securing a seat on the following bus if the first bus gets missed. The bus status and the availability of seats in the following bus can be checked online by using the redBus application. The Family Raya Ceria has just a single bus running in a single day for the route Bangko to Palembang. You can also contact the booking agency near you to get information about the same.