I have a customer who is BCM400, Rls 4.0. They are going to BCM450, Rls 6.0. The 450 box software level is listed as "10.0.1.02.120". What level is this? It came with a Rls 1.0 to 5.0 to 6.0 software kit. And do I have to upgrade it to 6.0 before I do the migration?