I would favor the trustee's estimate over your attorney's, assuming the difference isn't caused by delay within your lawyer's office, as the trustee knows how quickly he and the court can move - I suspect that your lawyer is simply being conservative in his estimate, or perhaps that he has experience with the trustee not moving as quickly as he promises. You would have to ask your lawyer to clarify any reasons for their difference in opinion.

Speed things up when a court is expected to act within two to four weeks? Courts don't move much faster than that.