Casual postal employees who had participated in an illegal strike on Monday had been given an ultimatum to return to work by 10am today, SA Post Office spokesman Lungile Lose said yesterday. Lose said attendance had increased yesterday and all of the casual staff on strike in KwaZulu-Natal had returned to work. The casual workers are striking to demand full-time employment in permanent positions. “The Post Office is considering all sustainable options, but is restricted by realities such as the cyclical nature of mail volumes and affordability,” Lose said. Areas that are affected are the Witspos mail centre in Johannesburg, the Tshwane mail centre and the units in Durban and Bloemfontein. The Post Office had applied the principle of no work, no pay, it said on Monday, when it cautioned of some disruption to services. Early last year a strike by casual workers over similar concerns caused a loss in revenue of R100 million for the Post Office.