There is a single rider queue, but IMO it will not be as effective as the single rider queue for Test Track (and MIB at USO). On Sunday, I joined the standby queue which was full up to just inside the doorway. A few people entered the single rider queue at about the same time. I ended up riding well before they did. Because M:S seats 4 guests per pod, there tend to be fewer single seats available when compared to attractions that seat 3 per row.