I just went through FRA yesterday. LH had issued my BPs all the way through my trip when I first checked in at NUE. So it was a big surprise for me to have the security check person in front of the RCC tell me that I have to have new BPs issued by United. There was no longer a counter in front of the RCC, so members/C/F-passengers were asked inside, others sent to the gate check-in. Everything worked smoothly, but still they told me NOW (winter+ extra procedures) a 45 min connecting time would be too short and no way one would make that connection anymore (even though it's still UAs policy for FRA connections).
Passengers still holding LH-BPs at the ID check in front of the flight's boarding area were sent to the gate check-in as well, even after they already started boarding.