Update:
UPS picked up my laptop 2 days after I contacted Acer, I received 4 text updates on my phone about repair progress, and was able to pick the notebook up again about a week after I sent it back. This was pretty fast, but I guess I was lucky they only needed to replace components that they had in storage (some year ago I had to wait 3 months with ASUS because they needed a component shipping in from China). They replaced the motherboard for one, I suppose it was indeed a sporadic hardware malfunction. It can happen I guess.