On Tuesday, the operator announced that the popular BIS, widely adopted by BlackBerry users, was coming to an end in its current format, and will be replaced by BlackBerry Absolute.
The new service will provide internet data access of 200MB per month after which users have to top up with a data bundle, or airtime directly.
According to MTN, the new service which replaces BIS will not have a major impact on consumers.
"Our analysis of usage behaviour shows that the majority of our BlackBerry customers fall within the 200MB usage pattern on a monthly basis," said Devan Chetty, general manager: Core & IP Planning at MTN SA.
During the first three months of implementation, set to begin on 1 March, users will be allocated an additional 200MB in terms of the service, MTN said.
"While features such as voice calling, video calling and screen sharing fall out of the BlackBerry Absolute price plan, MTN customers can utilise any of MTN reduced internet bundles or the free 200MB data allowance for these services," the company said in a statement.
The move follows the launch of the BlackBerry 10 smartphone that will not have BIS, but users were assured that the unlimited service would continue on the BlackBerry 7 platform.
MTN said it was working to develop cheaper internet access for BlackBerry devices and the company already has tiered service offerings starting at R14.95 per month.
"MTN will soon announce data rates to make internet connectivity even more affordable to BlackBerry customers," the company said.
The BlackBerry Absolute plan costs R59 per month.
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