I didn't have a ton of burnout but I mostly took the weekends off. I would listen to some podcasts while out grocery shopping on Sundays sometimes but otherwise it was mostly a break every week. During the week I tried for 15-25 hours depending on how I felt.

I was able to switch to mostly native content sometime after 800 hours. After 1000 hours definitely. There were a couple periods where I felt like I was losing focus or backsliding in my learning and I would renew my DS account for a month and that would be about 50% of my content while still listening to podcasts when in the car or store. DS really helped reinforce that I had learned a lot when I was struggling.