As of right now, nobody knows exactly how to get the Mystery Ticket required to get to Island 8, or the Aurora Ticket required to get to Island 9. The only way to get to Islands 8 and 9 as of right now is with a cheating device. However, it is very possible that Nintendo will have special promotions in the future that will allow people to get these tickets, kind of like the Eon Ticket in Ruby/Sapphire.