I think you found the answer. I did this too by fluke when i noticed my high performance was missing.
I reset the balanced and created a high performance, and again altered my preferred sleep times and actions.
since then, a day and a half its good!
I also ran the battery and windows store troubleshooters as part of the process.
I started to experience this with my week old Surface Book 2. I resolved this issue today with the help of this thread, but what worked for me was simply restoring the "Balance" power plan back to default settings. I've let the computer sleep a few times since then and I haven't seen the issue recur.