Other mistake: When Professor Potts bought Chitty from the Junkman and brings the car into the garage, the body of the car is charred or damaged somehow from the crash and fire. But the leather seats, dashboard and wooden steering wheel are completely unharmed.
Other mistake: When the Bulgarian soldiers storm the village to find the children, one soldier pushes open a door and the soldier next to him butts the already-open door with the end of his gun, making him fall forward slightly.
Other mistake: When Chitty Chitty Bang Bang passes the train on the first drive out there is no smoke coming from the train's smoke stack, meaning the train isn't running. Yet it is definitely moving.
Other mistake: In the scene where everyone is going to get away from Vulgaria in the car, Grandpa scrambles in after them. You can distinctly see a Vulgarian soldier give him a shove to get him in the car, then do his "Run away." thing.
Answer: It seems those times were occasions when she was on her way to see her father, Lord Scrumptious, at his candy factory, or wherever he may be (like at the Potts' wargaming with Grandpa).
Scott215