Welcome to South Africa ;)
Just some background regarding the situation, South African Express is not a subsidiary of SAA, but Mango is. SAX has close affiliations, along with Airlink, with SAA. Mango has gotten all of the Ex-South African Airways planes, and they have all been repainted. SAA did this to achieve and all Airbus fleet, so now they will be getting these 737’s back, and having to repaint them too, Along with all of SA Express’s fleet. (Reminder the SAX, and Airlink are operationally dependent from SAA).
I could see a merger between Mango and SAX as Mango is a profitable airline, but SAA is not. Thus creating more expenses which are not currently needed for SAA, as they themselves are on the brink of liquidation. SAX has had a history of financial issues, so this is not new. Even though they have acquired new planes.
Mango has also wet-leased an A320 which indicates a nice growth of passenger demand for them. But, SAX fleet has been grounded due to safety concerns, and other stuff of course (South Africa stuff), Cemair also faced the same issues earlier this year.
What will be nice is seeing the CRJ-700 in the SAA livery.
Below I have attached a photo from one aircraft of each airline:
The wet leased A320
South African Express:
Their new ERJ-190 (They also recently received a -175 or 170)
South African Airways
Other Articles that help to understand the situation