Bottom line - I didn't notice the initial error, my boss (who made the error) didn't notice, and if my reps DID notice they didn't point it out... but that doesn't mean they weren't, in reality, overpaid. We caught the mistake after about 3 weeks, when the other numbers for the month weren't reconciling...
So how would this be handled by your employer?
Your employer immediately deducts the overpayment from your checking, automatically, and then informs you afterwards that they've corrected the error.
Your employer notifies you that there was a payroll error, then deducts the overpayment from your next autodeposited paycheck.
Your employer shrugs and says, "Oops! Guess you win the payroll lottery!" sucks it up, doesn't ask you to reconcile the amount you were paid in error, and you just keep on winning!
Other (leave a comment)