This is going to be a short answer:
You have, I believe, a case to take to the CCMA for unfair retrenchment. If a company retrenches an employee and the reason they give that employee is that his position is going to be made redundant and a couple of weeks later, they hire someone to do exactly the same work, then they have obviously lied about that reason.
Take away the reason, and it makes the dismissal an unfair dismissal.
I suggest that you approach the CCMA with a view of disclosing a dispute. I would wait until the guy actually starts (if it is going to be within 30 days from last week Tuesday), otherwise, get very clear confirmation from somewhere that this person is going to start at some point in time and do the same work as you.
You would be allowed legal representation at the CCMA should you decide to go this route.
They (the CCMA) could award you an additional award of up to 12 months your salary, but more likely, this is going to be about 4 - 6 months. They could also order your reinstatement, should that be what you are claiming.
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