The below message was released by the IRS. During the below outlined times, returns electronically filed will not receive an acknowledgement until after system maintenance has been completed.
“Both the MeF ATS and Production environments will be unavailable for use Sunday August 18, 2019, beginning at 1:00 a.m. Eastern through 1:00 p.m. Eastern. Maintenance will be performed to ensure the system is functioning at peak performance.
We apologize for any inconvenience this may cause.”