This time in our structure help we take a quick moment to talk about the different between on time and in time.
When something happens on time, it happens at the correct time, the time it was planned, not early and not late. If you arrive on time, you arrive at the correct time, not early and not late.
On the other hand, when something happens in time, it happens with extra time to spare, earlier than necessary or required. So if you arrive in time for your flight, you arrive before the time required and probably have a few moments to go to the duty free shop or relax.
Here are some more examples.
The flight left on time. (at the correct time)
Due to the delays, very few flights departed on time. (at the correct time)
The crew arrived in time for their training. (before the last moment possible or necessary)
He arrived in time for his interview, so he sat and waited in reception until he was called. (before the last moment possible or necessary)
Have a great day!