Though there has been no official announcement yet from the government about the closures, this presumably is a cost saving measure. It also only seems to affect contract postal units, or CPUs, and not post office locations run by USPS.
In reports from local news outlets around the country, small business owners report that they have received notice that their contract with USPS to operate a CPU will be canceled. Many were not given a reason as to why it was cancelled.
In one report from Fox 10, a representative from the USPS issued a statement indicating that closing the CPU would help “fulfill our commitment to serve our communities with efficient and reliable access to retail services.”