From my experience and research, people will always lose muscle mass on a caloric deficit no matter what diet they go with. Depending on genetics, age and macronutrient intake, you can lose anywhere from 5-15lbs.
One tip to mitigate muscle loss during a caloric deficit is to drastically increase protein intake. Normally, .6-.8g of daily protein intake per lb lean body mass is sufficient for muscle growth. But in a caloric deficit and under 18% body fat, it’s advised to go up to 1-1.5g per lb lean body mass daily. I’ve also heard podcasts where natural lifters go to to 2-3g per lean body mass of daily protein intake when dropping under 13% body fat.
Fasting does help preserve strength (but not necessarily muscle mass) than other diet types. But just make sure you keep lifting frequently and focus on maintaining your compound lifts.
Decide how important it is to you to lose that weight. You can always build muscle again. People are afraid of losing muscle on a dry fast but it isn’t like a water fast - you are burning fat. Unless you plan on doing an extended dry fast of like 12+ days, you will be fine. And you can always rebuild. Fasting is a time of rest and healing - personally I would say it’s better to allow that to clean out the body and then return to strength, which will easily still be there again. There’s nothing to be afraid of