hate to dissapoint you, but IAD hasn't seen the LH A332s for a looong time now...I think they stopped flying them in about 2-3 years ago. One thing I do know is that LH416/417 will be operated by an A333 this summer! Flight LH418/419 will continue to be operated by the B744s.Hope this helps!
LH 346 is configured C/Y, thus would be a downgrade to JFK. A Lufthansa A340-600 will not be seen at John F Kennedy. Most Likely 3x daily 333 operation, maybe 744 F16/C80/Y234 (new config) during the summer.