We're running Oracle Enterprise 12.1 on Linux and it appears that if job_queue_processes=0 on the standby database, that the non-sys scheduled jobs go away when the DB is opened.
I've been using job_queue_processes to limit the job execution vs DBMS_SCHEDULER.Set_Scheduler_Attribute('SCHEDULER_DISABLED','TRUE') because I can set the standby differently than the primary. Has anyone else seen this behavior and is it a bug?