The proposed 2019 United States Postal Service rates have been published, or have they?

The USPS proposal to change First-Class Package Service in 2019 to a zone-based service could have profound impacts on stamp dealers selling on
eBay and other web sites. Will the USPS continue to accept stamps for this service? While many stamp dealers continue to use Certified or Registered mail, First-Class package service provides an economical alternative with tracking acceptable to philatelic insurance providers.
Now, a First-Class Package with tracking can be mailed anywhere in the US for $3.50 retail. Stamps can be used. Negotiated rates are much lower, usually about $2.68. The extreme disparity between retail and negotiated rates opened in the last two years as rates were dramatically increased. Rates have nearly doubled in the last five years.
Published news reports tend to ignore First-Class Package service rates, leaving up to dealers to scramble in January to get information on new rates. If the structure of the service is changing, when will we find out?