A huge portion of USPS international package volume is “ePackets” from China. These are a special service provided by USPS since 2011 for Chinese/HK goods that are cheaper and faster than normal USPS international shipping.
These ePackets are then bundled up into big sacks that are basically not inspected at all at US international mail facilities due to the de minimis exemption, which was just rolled back. The special status granted to ePackets meant that the volume shipped grew far beyond the processing capacity for normal packages at US IMFs. This pause (and subsequent unpause) from USPS on packages from China is because they don’t know how they’re going to handle that volume if it isn’t given special status.
Source: I worked on a project adjacent to this a couple of years ago. Close enough to pick up the basics but this isn’t quite what I was working on, so take my comment with a grain of salt.
These ePackets are then bundled up into big sacks that are basically not inspected at all at US international mail facilities due to the de minimis exemption, which was just rolled back. The special status granted to ePackets meant that the volume shipped grew far beyond the processing capacity for normal packages at US IMFs. This pause (and subsequent unpause) from USPS on packages from China is because they don’t know how they’re going to handle that volume if it isn’t given special status.
Source: I worked on a project adjacent to this a couple of years ago. Close enough to pick up the basics but this isn’t quite what I was working on, so take my comment with a grain of salt.