Almost 30000 taxpayers submitted their returns via eFiling in the first nine hours of the 2015 Tax S.
Jabanga, who is the Gauteng Striders chairman and a member of the Central Gauteng Athletics' executive committee, was spotted chatting to fellow board members during the national cross-country trials at Boksburg at the weekend.
"He was at the finish area," said one coach who asked not to be named, adding that some CGA board members had claimed they had heard rumours of his suspension, but had not received official confirmation.
Jabanga gave tablets to top runner Lebogang Phalula before a 10km road race in August 2011, and she tested positive for the stimulant methylhexaneamine. She was banned for three months in 2011, but the World Anti Doping Agency appealed the punishment which was upped to two years, one of which was suspended. The ban was backdated to 2011, which meant she did not have to serve extra time.
CGA president James Moloi, who said he missed the trials because he was ill, explained he had learnt of Jabanga's ban only when he returned to the office on Monday.
"The (CGA) general manager couldn't communicate with the board members," Moloi said. "Only I can - so he couldn't do it last week. Starting from this past Monday (Jabanga), knows his story. We had our first board meeting of the year on Monday, and we suspended him."
Jabanga's lawyer Moses Rankooa said he was reviewing his client's sanction, and assessing if he had been given a fair and proper hearing.