Well . . . I'll tell you that you absolutely CAN do it. If you said I only had to lose 15 pounds in seven weeks, I'd be ecstatic. However, it depends on your mental fortitude. It's also physical hell, but that's different. That's bearable. It's the mental toll that will screw you.
I mean, I'm not your coach, but I got super shredded in under 7 weeks with no muscle loss (at least, not visibly). So, I'll just rehash a bit of how I did it:
Cut cals to the bare minimum. By that I mean 1.5g of protein per lbs/LBM (even up to 2g). Absolutely no more than 40g of fat per day, and that was pushing it. Zero carbs, except for tagalong carbs that you can't get rid of completely. This ends up being an absurdly low calorie intake per day. 6 grams of fish oil per day is mandatory. And my supplement stack was ridiculous -- 2 caps of green tea extract, about 1200 mg caffeine (although research says than 200 mg x 3 is the maximum effective dose, it was too low for me), 3g HMB (which works, but only on a cut as a muscle-sparing agent ... HMB is useless at any other time), Bronkaid 3x a day (although if you're on Clen, you won't need this), Calcium/Zinc/Magnesium supplement, tons of glutamine, 5g creatine & 5g beta-alanine 4x day, double dose of vitamins, 15mg melatonin and 1 cap of HTP to maintain sanity (both are mood-boosting agents... and the melatonin I take has L-theanine in it, which counteracts the stimulatory effect of caffeine, so I could maximize my time on the caffeine every day, right up until I went to bed... then I'd pop the melatonin and be asleep within the hour. And melatonin has heart-protective effects, which you'll need on such a drastic cut.).
But wait . . . it gets worse! Yay!
Either volume has to go up, or frequency has to go up. I was in the gym 7 days a week, lifting for 6. Basically alternating between hitting the major groups and then using the following day to hammer the minors. One rest day.
Cardio every day, in some form. At least 5 times per week, an hour of interval-ish training. So, I would do Lyle's Stubborn Fat Solution. I did this all on a spin bike, btw, because 1) I hate running, 2) I hate running outside in the heat, 3) I'm way faster than a treadmill will go, and 4) It's easier and faster to speed up and slow down than any other machine in the gym, and the easiest besides running outside, which, see 1 &2. Basically 10 minutes of as high intensity as I could make it for the first part -- 15 seconds on, 45 seconds rest. Then 40 minutes of medium intensity steady-state. I tried to keep my HR in the 110-120 bpm range. And then the last 10 minutes were 30 seconds on, 30 seconds off of more intervals. Lyle says to do 70%, but I was going as hard as I could maintain for those 30 seconds. It's a bitch. And I did that 5 days a week, plus soccer. The only two days I didn't do that was my lifting rest day (in which case, I did 2 hours on the bike of steady-state), and days when I had more than one soccer game.
This will absolutely get you shredded. But it's ****ing hard. And you'll have to reverse-diet your way back up. My problem now is that because I cut calories so hard, my body got SUPER efficient at burning fat, effectively lowering my BMR. So, it isn't that my metabolism is DAMAGED (this doesn't happen); it's just way more efficient than it needs to be. I now have to slowly increase the cals every two weeks to reacclimate my body to using more carbs and slowly away from the fats (all the while keeping the fats as low as possible).
Also, all this activity mandates a weekly refeed. You just can't get away without it until the last week, when you can switch to a 2 week cycle, and then do the refeed before the show.
Because of the increased volume and/or frequency, you won't lose much mass (if any, but it isn't noticeable). The hardest part is just mental. It will **** with you. Especially on the steady-state cardio part. I was just angry while I was doing steady state cardio. "THIS IS ****ING BULLSHIT! OMG, IT'S ONLY BEEN 1 MINUTE SINCE THE LAST TIME I LOOKED AT THE CLOCK!" Every. Damn. Day. For the whole time.
The results are so worth it, though.
Again, I'm not your coach . . . just personal experience of doing this for 2 summers now, and doing it quickly.
Last year, 7 weeks:
This year, 6 weeks:
I know you need to be leaner than this to be show-ready, but I'm also assuming you're starting at a lower BF% than I did.