Thank you for all of the advice

Unfortunately, I have tried on a few occasions today to get through to the German call centre, but when I phone up I'm told that due to an overwhelming number of calls I should phone up later. There is no option to hold and wait.

In the end I phoned the number for Italy. They confirmed that the ticket has not been reissued (even though I have been told twice that the ticket number is all fine). The agent did say he would contact the ticketing office, however, after being placed on hold for no longer than a minute he said he'd spoken with them and they'd be unable to reissue it due to an overwhelming number of requests in the queue.

I did mention that I hoped the ticket would be reissued in time - at which point he admitted this had been a problem over the summer, but he was confident my ticket would be reissued at least 2 weeks before departure. So that's reassuring, I suppose.

It is what it is, I just don't want to get to the airport and be unable to fly in Y, never mind J! I have had a few instances of this with Iberia, but it is always resolved with a 5 minute phone call and the tickets then being issued instantly, but with Lufthansa it seems to be a slower process.

Thank you again for the replies