I have called Lufthansa numerous times about various items, and always asked about the phone checkin. Some reps told me checkin begins 24hrs in advance, but others have said it's day of departure (at midnight tonight). Some have said they can check me in with a UA codeshare #, some have said they can't.

I am so confused as to what I can/can't do! I just want the bulkhead seats!!!!

Sounds like this telephone thing is a newer feature, and maybe there's some confusion about the rules. I think the common theme was that the flights to/from North America are treated differently than inter-europe flights.