Did it all through recovery as part of the Cdnuts protocol and it’s fantastic if you have carb insensitivities. If I eat carbs at lunch I normally get sluggish, and did before PFS. With doing almost full keto until after dinner, I stay very lean and it doesn’t affect me much.
The only issue with backloading is sometimes during the mid afternoon you get some of the issues of low carb diet (bad thyroid function, running on adrenaline, etc.)
Other than that however, it’s been a fantastic diet staple for me during and after recovering.