FedEx SmartPost (now called FedEx Ground Economy) was still being delivered by USPS up until recently also. We buy from a place that still ships saying it is FedEx Smart Post but the last package was delivered by FedEx and never got the secondary USPS label. In the past, the exchange would happen in Fort Worth and would be here two days later. This time it took two days to get out of Fort Worth and another 3 days to get out of Lubbock and to us ( so 3 days longer than before).
Had a USPS package going to Hawaii from Texas with transit time of 5 days. After 5 days, it scanned in Brooklyn NY (should have went through Los Angeles). This is our second package to Hawaii that has been miss routed away from the destination.
USPS stopped handling any UPS about a year ago in this area.