The Hearst Corporation commissioned the review last year as part of its plans to renovate the historic structure in January 2020.
The U.S. Postal Service of San Simeon is located in the Sebastian Store but its lease was set to expire in January and would be not be renewed as renovations got underway.
But after the review found structural deficiencies in the more than 150-year-old building, the Hearst Corp. and USPS decided to close the building early.
“The building is not safe for habitation,” USPS Real Estate Specialist Dean Cameron said Wednesday in a phone interview.