Originally Posted by
cvision
… how a 30 minute delay on the inbound translates into 3.5 hours the next day is hard to explain by this…
The OP’s nephew was booked on LH809 ARN 06:45 - FRA 09:00 on 23 Dec.
The fact LH808 on 22 Dec which was scheduled to arrive at 23:50 was 31 minutes late is not relevant to this discussion. Even if the flight arrived on time crew from that flight couldn’t have been rostered to operate LH809 departing at 06:45 on 23 Dec.
I suspect crew on LH806 which is scheduled to arrive at 15:35 or LH804 which is scheduled to arrive at 18:05 normally overnight in ARN to operate LH809 the following day.
Since LH806 on 22 Dec was cancelled they were one set of crew short in ARN and LH had to wait until the crew from LH808 had sufficient rest time before they could operate LH809, hence the delay of 3+ hours.
I hope the OP will report back how his nephew’s claim goes.
P.S. some info on the cancelled LH806 on 22 Dec in this post.
https://www.flyertalk.com/forum/35848681-post1.html
LH806 has several delays: first the crew is late, then the catering is late, at this point they've lost their slot time and the next slot they're given is 15:00, a few minutes later the flight is cancelled.