Odds of Hanging On
The best way to get sacked from this job is to prove yourself incompetent. If you show up every day, get the work done, and don't cause any disasters, you shouldn't have any trouble holding on to your job. Until, that is, and not to beat this point into the ground, the day the machines take over. It really isn't that unlikely that a day will come in your lifetime that a computer can do this job better than a human. Until then though, business is good.