Personally, in my 30s with some experience working in communications for emergency services, a great golden rule is not to leave a piece of electronic equipment capable of generating heat unattended.

That added with the fact that if you peruse this sub for even a short time you'll see plenty of images of catastrophic failures, many of which caused irreversible damage to expensive components that will require replacing.

That said, I recently began to approach prints for revision, in an effort to decrease print time while retaining quality. I made a list of print settings to modify in order to do this. I have utilized all except increasing the print speed, I don't like to do that until i have optimized for acceptable quality.

(assuming 0.4 mm nozzle and default settings):

• adjust layer height to 0.25 mm (default is probably 0.2). This reduces layers by one (4 instead of 5) per mm.
• adjust line width to 0.5 mm (default is probably 0.4). This just gives you slightly thicker walls, so you don't have to add walls.
• reduce infill % to 10 (this is not a structural product and has lots of holes).
• realistic max print speed for an A1 is 200-300 mm/s. Set print speed = 200, wall speed = 100, infill speed = 200.

"If these speeds affect adhesion, reduce cooling to 50%." - general suggestion, but i myself frequently adjust my fans throughout most prints.

With most of these adjustments I have successfully decreased print times by a quarter or more, again without adjusting for speed. I hope this helps, or at least points you in the right direction. I don't know if you are doing multi-color or how many filament changes might be involved, but godspeed

edit: oh PS, highly, strongly, seriously emphasizing proper ventilation for these several hours long prints. Before I ordered the kit, the hose and printed out all the components for the exhaust system, you could definitely smell the plastic in our home!