How is “start on at” used?

In Ford v Ferrari (2019), one line is: “We start at the start line.”

Which movie is “start on at” from?

The clip at the top of this page is from Ford v Ferrari (2019).

Phrasal verb

to begin to complain about sth or criticize sb

informal · Heard in 1,041 movies

start on at sb (about sth)
to begin to complain about sth or criticize sb
She started on at me again about getting some new clothes.

Definitions from the Oxford Advanced Learner's Dictionary, 9th edition

We start at the start line.

Said in 8 films · #1