We are facing the exact same issue. Every time we receive a review and reply on the same day or the next, we have to wait over 15 days for a response. The only way we've managed to get feedback is by filing direct complaints about the excessive review times. Only then, the day after the complaint, do they process the app and reply. Right now, I've been waiting a week for a response to my latest submission, so I'm going to submit another complaint, and I'll keep doing so until it gets approved.