Is there an actual manual; online that details what all the functions are on the control panel? As in (today’s wonder) what speed settings are affected when you adjust the speed (the little rocket ship)? Is that the fans, the motion, the extrusion?
I have tried searching without success for anything - all I get is the “Quick start guide”
Help?
Yes, a full and very detailed, ever increasing wiki.
Enjoy.
But no search or reading has yet revealed what the little rocket ship ACTUALLY does. Surely there’s more than just the Quick Start Guide available for this.
The P series has a rather unfortunate display that does not have the extra space the A or X series do to provide more information.
The rocket ship (speedo on A & X series) denotes the speed of the print.
The default is “standard”, this is the normal speed of the printer, designed to provide the best blend of speed and accuracy.
There are four settings for speed in total.
If you have an extremely delicate print, swapping it to silent mode will aid in potential success. As the name implies, it is much quieter.
If you wish your print to be completed more quickly at the potential expense of some quality and increased noise, use this.
If you wish to see your printer work at a speed that should in all fairness force the print head to detach from the printer, go for Ludicrous (it will not). It is noisier, much faster, and more prone to details not being perfect. Yet, astoundingly fast and decent-looking prints.
The fast Benchy models use this.
I have a P and A series printer.
Thank you. That explains it very nicely. 
You are very welcome, I am happy I answered it for you.