While you should by and large stick to the arrangement, you should also recognize that there are rare, special times when employees will need a bit of extra time off and there are times that the company will require employees to give it extra hours. The company should pay for above-normal work one way or another, and employees should be docked for below-normal work. The give-and-take should roughly equal out over time. Within reasonable boundaries, nobody should worry about the exact ebbs and flows.
