He was hauled straight back to the hearing to explain the tweet after the disciplinary panel found out about it but another hearing was scheduled because Hughes' counsel had already left, the Rugby Football Union said in a statement.
At the second hearing on Wednesday, Hughes' ban was extended to six weeks.
Hughes gave evidence that "his guilty plea had only been entered on advice and that he did not genuinely believe that he was guilty of the offence in question which ultimately led to his frustration as expressed in the tweet," the RFU said.
"Whilst the panel accept that the tweet was written in a moment of frustration and was deleted quickly by the player, it had already been picked up on social media and was then discussed publicly.
"The panel make it clear that tweets and comments such as this undermine the game, the core value of respect and the disciplinary process."
Hughes' back-dated ban will run until Nov. 20, making him eligible for selection for England's test against Australia on Nov. 24.
(Reporting by Ian Ransom in Melbourne; Editing by Greg Stutchbury)
