Imo the levels are perfect for a 60 day diet IMO...Muscle loss will be at a minimum if weights are kept high and protein intake in kept moderate.
What you lift does not imply how much muscle you have, however in this particular case there is two reasons why I should be weaker week after week.
1. Because my body weight is dropping
2. Because I am consuming overall less calories.
So here is what I propose, I will try to increase every single lift on every single exercise. Example I am doing 315 on bench for 15 rep, I will try to get to 20 reps. I do deep squats (ass touching the floor) with 365 for 12 reps, I will try to hit 405 for 15 reps. You get the point.
If I can pull this off despite dropping 40 lb and being on very low calories then it is safe to say, given my situation that I did not lose any muscle.