Steal a march upon (someone or something) phrase
To get something that helps you to be better or more successful than someone before they do.
I'm sure that I got the answer before John, but he succeeded in stealing a march upon me by saying it to the teacher before me.
That dress is one of a kind. I loved it, but I didn't bring enough money to buy it. Then that woman stole a march upon me by purchasing it ahead of me.
You should use that limited discount code quickly; otherwise, someone could steal a march upon you.
The verb "steal" must be conjugated according to its tense.
This phrase originates from medieval combat, when a day's march was the maximum distance an army could cover. An army might surprise and overtake the adversary at daylight by advancing silently at night. It was first used figuratively in the second part of the 1700s.
To be dishonest or deceptive and no one can believe
No one believes what she said. She couldn't lie straight in bed.