If you want to lose weight, you’d better avoid special “low-carb” products that are full of carbs. This should be obvious, but creative marketers are doing all they can to fool you (and get your money). They will tell you that you can eat cookies, pasta, ice cream, bread and plenty of chocolate on a low-carb diet, as long as you buy their brand. They’re full of carbohydrates. Don’t be fooled.
If your goal is to get leaner and not lose muscle in the process, then I’d recommend sticking to slow consistent fat loss and not try to rush it (that will just impact strength even more, which increases the potential for muscle loss). Keep doing what you’re doing, and take 1-2 week diet breaks when needed (go back up to maintenance or possibly a very slight surplus).
What does a HIIT workout look like? You could jog for two minutes, sprint for one minute, jog for two minutes, sprint for one minute. Or you could do a HIIT workout on a bike, or by running up stairs and then jogging back down. The key is that you go relatively all out for a short period of time, then recover by maintaining a moderate level of intensity, then go again.