The low MU fares from MOW to SE Asia have been there for a long time. Never disappeared.
The code sharing agreement with SU is not extended yet beyond Summer 2017 timetable, so this is the limitation.

Frankly, MU is another airline that manages SU codeshares in a weird way in my view. I guess like Alitalia the bottom line from this agreement is hugely negative for MU however they do not have proper accounting to tell this