The Brazilian tested positive for the performance enhancing drugs drostanolone and androstane prior to his January 31 fight with Nick Diaz at UFC 183, and later failed a test for Oxazepam and Temazepam, drugs which are used to treat anxiety and sleep difficulties.
Silva stated in March that he had ordered the testing of a number of medications and supplements that he had taken while recovering from the broken leg he suffered at UFC 168, his last fight prior to the bout with Diaz.
It was these tests that resulted in the initial postponements to the hearing, but there has been no indication of why the hearing has now been postponed once more.
Silva's team now have until August 7 to submit their defence. The 40-year-old maintains that he has not taken any banned substances.