USPS Ground Advantage

Hi Everyone,

I guess today USPS released “USPS Ground Advantage” which replaces USPS First Class Pkg, Parcel Select, and some other options.

I do not see an area on Amazon where I can change my shipping settings, and they are defaulting to either USPS Priority or UPS Ground. We ship a ton of tiny items, and this is going to kill our margin.

Does anyone out here have any idea how we can change to default to Ground Advantage?