I booked my parents with first class award tickets from RDU to BOM recently. It was fairly close to departure (end of January), and they just started their trip on Apr 10th.
Anyway, the only flight available trans-Atlantic was IAD-FRA on a UA 763. Without many other options for other days, I went ahead and booked them. A nice 1K perk is being able to change award tickets without any fees, so I started calling about every week to check current award inventory.
After a couple of weeks, I was able to change the return FRA-IAD flight to a UA 744. Not LH F, but better than UA 763. However, I couldn't get any luck changing the IAD-FRA UA 763.
About 4 days before their trip, I called to check on another leg of their trip, and was surprised to find out that somehow they had been waitlisted and cleared for LH 419 in F (IAD-FRA). I had long since given up on any LH F opening up trans-Atlantic, and Star Alliance itineraries aren't even supposed to allow waitlists.
Not too sure how it happened, but it was a nice Easter surprise. I got a nice e-mail from the folks while they were relaxing in the FRA F lounge, saying that the LH F flight was the best they had been on. And they were about to jump on another LH F from FRA-BOM.
Moral of the long story: I'm glad my folks didn't have to experience UA 763 F.