There is one circumstance where SubAssistant does not notify you of a job and that is if the job is locked. As you may know,  a job is locked in SubFinder if the job is actively being called out, someone is viewing the jobs details online, or someone is listening to the job details by phone. SubAssistant does not notify in this case because a sub cannot pick up the job while it is locked. SubAssistant will wait until the job becomes unlocked before sending the notification. However, we've found that, often, if the job is locked because it is in callout, the job will be picked up by a sub who was called. This would mean the job would disappear from the available list without ever becoming "unlocked".