Don't think. Know!
Welcome. If you're going yo argue with JLR about this, you need to know every little detail. If you say to them or anyone else , "I think", they have you for breakfast, spit you out and then have you for lunch.
Make sure your dad didn't miss a service request. Don't know about the newer ones, but on my L322 , you have to be quick to see the service due message.
Iam sure someone else posted something similar a couple of years ago. Maybe have a search see if they posted the outcome.
Good luck whichever way you go with it.