Unlike you I contacted the AMA and asked specifically about the 400 ft limit and received this PDF file which is a letter from the FAA to the AMA re its members to fly above the 400 ft limit. Notice I said members it looks like non members will have to abide by the 400 ft limit. Reading it over non members may be able to fly over the 400 ft limit but must follow the safety guidlines of a community based CBO such as the AMA. Does this mean the FAA in wording the AMA as a CBO recognize them as such????????????