As beings made out of patterns of xenon energy, the biological metaphor for teleopolan citizens is always going to be limited. What we might refer to as the external coloration of a Teleopolan is not in fact a property of the teleopolan itself. This is to say, there is no "pigmentation" of a teleopolan "on its own" without an eye to the position of the teleopolan within the processes which it has found itself involved in. Generally in a moment of observation, teleopolans resolve to be either blue or green, although at the start of their life cycle they are gray.
This moment that is witnessed by the external observer as a pause or "stutter" in a continuous simulation is understood by teleopolans themselves as a unit of labor-time. From moment to moment in labor-time teleopolans may swap positions within a process and may or may not swap their mood tone as their physical position changes. Teleopolans seem to alternate mood-tone with a consciousness towards the observer, so that if multiple teleopolans are overlapping eachother, one will be blue and the other green. From outside of the paradigm of labor-time it may seem that Mood-Tone can change in an instant, as a moment of labor-time is equivilant to about a millisecond in the Teleopolis simulation.
Another interesting effect of teleopolan Mood-Tone is that it seems to remain consistant across multiple images of the same Teleopolan. For instance, if a group of Teleopolans is engaged in a productive activity in a room that contains a photo of the same teleopolans engaged in a leisure activity, and every Teleopolan has a photo ID in their pockets, the Mood-Tone of each teleopolan will change across all images without regard to the Mood-Tones at the time the images were taken.
The trouble with conceptualizing Mood-Tone speaks to a larger problem with understanding teleopolan metaphysics. To the teleopolan, the idea of isolating variables or even attempting to understand something free of its full context is nonsensical. A teleopolan existing without engaging in leisure and work activities is hardly a teleopolan at all. We might speculate that a Teleopolan left by itself, in an empty room, might return to a youthful grey. However, no instance of such a thing happening has yet been recorded in the 3.5 million labor-years simulated in Teleopolis to this point in time.