There is not. We did the same thing you had setup in Forms 9. So when we switched to Forms 10 all of the users tasks were in the Available tab. We first went into every process and removed the backup user because they are not needed anymore in Forms 10 because it no longer terminates the task and an admin can reassign tasks if necessary. After we removed that backup user from all user tasks we instructed users on how to go to the Available tab and assign the tasks to themselves. Since then things have been smooth sailing.