I got this email from usps:
This is a final reminder that on January 17, 2016, in conjunction with the USPS Price Change, USPS will implement updates and additional features to the suite of Web Tools APIs. Updated release notes are available now at usps.com/webtools. Impacted APIs will include, but are not limited to, the following:
Domestic Price and Label APIs
International Price and Label/Customs Forms APIs
The Web Tools external testing environment is now available. For instructions on accessing the test environment, please see the release notes under the Announcements section at usps.com/webtools.
Is marketpress ready for these changes?