She headed to the front of the building to investigate when she heard a loud boom and saw a yellow school bus crashing through front wall into the lobby.
Fortunately, the post office was not open at the time of the crash, just before 7:30 a.m. Tuesday. Dellinger was the only one inside.
None of the 17 students - heading to the York County School of Technology - were injured when their bus collided with a pickup on Delta Road, near Muddy Forks Road in Chanceford Township, before hitting the post office.
"I am thankful God did not choose today to be my last day," said Dellinger, who has worked for the U.S. Postal Service for 27 years, including 17 years in Brogue.
The bus was carrying 17 students, who ride the bus from the South Eastern School District to the technology campus in York Township, said Dr. James Kraft, director of the school of technology.
"We're glad none of our students were injured. We hope the driver's injuries are not severe," Kraft said.
The bus driver, Michael Reigart, 27, of York, broke his wrist and had a gash on his head, said Jean Parks, communication coordinator for the school of technology. The driver's younger son, who was riding in a child safety seat, was not injured in the crash, she said.
The bus is owned by the Durham Bus Co., a York County company contracted to transport school of technology students, Parks said.
According to state police, Francis Grove, 69, of Chanceford Township stopped on Delta Road and was waiting to make a left turn onto Muddy Creek Road when she was hit from behind by the bus. The bus then crashed into the post office, police said.
The school bus driver swerved to miss a pickup, and clipped the truck in the rear, before crashing into the post office, according to state police.
A substitute bus was sent to Chanceford Township to pick up the students. Five students were checked out by a school nurse and attended classes while the remaining 12 students were picked up at the scene by their parents, Park said.
The crash knocked a 12-foot hole in the wall, causing the brick façade to collapse. The bus hit and pushed the lobby's front counter several feet. Cinder blocks landed in the lobby area and on the counter.
A structural engineer will examine the damage as the post office determines its options, said Michael Becker, the postmaster from York. The front of the building will be boarded up until repairs can be made, he said.
The Postal Service said pickup and delivery services will be transferred to the Red Lion post office.
Dellinger counted her blessings.
After the crash, she called her husband to let him know a bus crashed into the post office.
"I told him a bus came through the post office and I was OK," she said.
Dellinger said she didn't want to think what could have happened if the post office was open and busy with customers.
"It could have been a lot worse," she said.
BROGUE MOVES POSTAL SERVICES
Brogue area usually a place for quiet sight seeing. Read more at York Town Square blog.