Think this is leisure given the timing and I am sure United will not have trouble filling up Y -- LH's MUC flight is more awkwardly timed for connections elsewhere in europe (arriving late the following day), and UA will have fewer seats filtering through the LH system via FRA as the 747s come offline. Net net I think the route will do fine; if they can fill the seats upfront with biz pax it'll go y/r.