The corporate action refers to a year-long bidding war for control of RBPlat between fellow listed platinum group metal (PGM) miners Northam Platinum and Impala Platinum Holdings.
Northam recently withdrew its purchase offer, citing low PGM prices.
The executives, Steve Phiri and Neil Carr, who retired last year, had previously agreed to sign fixed-term contracts to make sure organisational stability until April 7; however, the corporate action had not been completed.
Notham has not stated whether it intends to keep its 34.5% investment in RBPlat.
Meanwhile, Implats extended the longstop date for its bid to buy out all shares of RBPlat that it does not hold to April 28.
It currently owns 41.5% of RBPlat.
Mathew Nyaungwa, Editor in Chief of the African Bureau, Rough&Polished