Yes, I have noticed that my cameras sometimes switch from HD where I set them, down to 360p without anyone personally changing it. I wondered why.
I hadn’t really paid close attention to when this happens (ie: after a restart like you said, though I am glad you mentioned this might be the cause),
I just noticed that sometimes it happens, so I have been checking them occasionally to see if I need to manually reset them back to HD. It is mildly annoying, and I assumed they’d get around to fixing it. I didn’t try to figure it out. I also didn’t mention it in a post, because it seemed like other posts I made about issues I found were completely ignored, so I just didn’t bother posting about it. Glad someone else noticed this issue and mentioned it though. You are not alone.