Is there a reason most people use Cleanup Mode, as compared to Speedrun Mode? I noticed through a small amount that there seems to be loads, or something of the sort that adds an additional few seconds to the run, where you do not have control yet, or lose control of your character in cleanup mode to load into the office area.

I haven't tested it myself but it shouldn't affect the time on the result board afaik.

These videos seem to show that there is some sort of discrepancy between using the speedrun mode times, versus cleanup mode times. Cleanup mode seems to add 2-3 seconds or so. Speedrun mode also allows for more precise timing, giving us hundredths of seconds if we use the same frame the score/time screen shows up on the monitor.

Additionally, speedrun mode eliminates jamming of the bucket machines and the bin machines, removing some annoying RNG