Confused about Amazon handmade fees

I sell handmade lamps mostly on Etsy, I signed up for an Amazon Handmade account a few years ago and didn’t sell much. In the last year I have been selling my surplus lamp parts on Amazon in non-handmade categories. I have a professional plan but I’m not paying a monthly selling fee as I’m registered for Handmade. If I understand it correctly I’m paying a fixed percentage fee for each sale (about 12-15%) plus the digital services fee, so for small items it ends up about 18% fees. If I’m selling £1000 worth of goods a month that’s roughly £180 fees. If I deregister for Handmade and pay the monthly fee, would my per item sales fees be reduced, based on selling £1000 of items a month?