The following is the Oct. 29, 2020 Government Accountability Office report, Navy Maintenace: Navy Report Did Not Fully Address Causes of Delays or Results-Oriented Elements.
From the report
The Navy’s July 2020 report identified two key causes and several contributing factors regarding maintenance delays for aircraft carriers, surface ships, and submarines, but did not identify other causes. For public shipyards, the Navy’s report identified the key cause of maintenance delays as insufficient...
https://news.usni.org/2020/11/04/gao-report-on-navy-maintenance-delays