Thanks, Damiross and MRGoodwin

Thanks to you both for your informative replies.
No need to explain the comment, Damiross; I’m a teacher, so I knooooooow where you’re coming from.
MRGoodwin, I’ll check out that link the next time.
Yes, my son landed safely at the scheduled time. I was a bit uneasy (I can now understate that fact), because I’ve used Flight Aware for about 2 1/2 years, and I’d never encountered this problem.
Have a great evening, both of you!