upset (one's) applecart

upset (one's) applecart

To ruin or interfere with one's plans or goals. Look, he's not trying to upset your applecart or anything—he just needs to meet later in the day now, that's all. I had some ideas on how they could improve things, but I didn't want to upset their applecart this late in development.
See also: applecart, upset
Farlex Dictionary of Idioms.

upset the/somebody’s ˈapple cart

(informal) do something that spoils a plan or stops the progress of something: Another, much cheaper hairdresser has opened next door, which has upset the apple cart.
See also: apple, cart, upset
Farlex Partner Idioms Dictionary
See also:
  • upset the/somebody's apple cart
  • upset the apple cart
  • upset the applecart
  • upset the applecart, to
  • (one's) applecart
  • applecart
  • upset (one's) plans
  • upset plans
  • bane of one's existence, the
  • copybook