This is mere deductive and un-collaborated observational research, but:
There are a great many fine colors available to use as Map Markers. As you have noted;
red is residential only
green is commercial only
yellow is residential & commercial
blue is refrigeration only
All the other colors, despite being available, remain un-assigned. These are:
purple X Reset
yellow X Reset
light green X Reset
light blue X Reset
light purple X Reset
white X Reset
brown X Reset
black X Reset
grey X Reset
orange X Reset
red dust X Reset
spring X Reset
maize X Reset
olive X Reset
tree X Reset
forest X Reset
mold X Reset
teal X Reset
sky X Reset
cloud X Reset
lavender X Reset
fuscia X Reset
sunset X Reset
burgundy X Reset
lilac X Reset
sunflower X Reset
candle X Reset
Although I can be lucky at times - my interim conclusion that the use of any marker colors other than red, green, yellow, and blue indicates that the map-organizer did not know the specific-work details of the person/company being assigned the mark at the time of assignment - is the casual work-product of mere speculation.
Last edited by Poodle Head Mikey; 05-01-2022 at 11:01 AM.
PHM
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When faced with the choice between changing one's mind, and proving that there is no need to do so, most tend to get busy on the proof.