Chiming in as a serial single rider along with my other family members at times- we have been Engineers probably 99% of the time, and were also Engineer most times when using LL but as a single rider. The CM on one occasion was flat-out telling the single rider line that we would all be engineers. So, I would say that you should expect to be an engineer using the single rider line and whatever position you ask for if you are in the regular line, since then you can request the job you actually want to have

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