Earlier, it was reported that lunchtime picketing in a wage dispute would start on Monday.
But Mwasa spokesman Ernest Dlamini said a media release announcing the labour action contained the wrong date.
"The picketing is going to start on Wednesday during lunchtime and continue on Thursday and Friday," said Dlamini.
"Next week, Tuesday, we will be having a march," he added.
Mwasa earlier said it expected all of its 600 workers to take part, while the Communication Workers' Union (CWU) said around 1000 of its members would participate.
The SABC has just over 3000 staff members.
The unions went to the Commission for Conciliation, Mediation and Arbitration when the SABC revised a 12.2 percent multi-term pay offer it was supposed to have implemented in April, to 8.5 percent.
The Labour Court in Johannesburg dismissed a bid by the SABC last week to stop its workers from striking.
The protesters were expected to picket around lunchtime, would not work overtime and would only do the duties in their job descriptions.
If there was no progress in negotiations with the employer, a
complete stay away would start on 13 July, unions warned.
Sapa
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