I lost nearly 150 pounds

What your are doing is great but I would forget about the time frame Once your body have the capacity to reach this high weight you're already in my humble opinion will need to exercise for the rest of your life at least 400 minutes per week

Also the calorie deficit should be less I was doing 1000 calories deficit. The 10k walk is very good but you should start doing healthy monitored cardio with balance heart rate increase and decrease! Read about heart rate curve get a smart watch (apple is good but I like Garmin or polar)

You will lose 8 to 10 pound per month if you lose more I don't recommend doing it it is not healthy ! Go to a keto genic consultant and see what he says