Sangha Town is approximately 1200 kilometers in linear distance from Ad-Damazin and about 1400 kilometers from Niger Base.
The F-16's combat radius is at most 1000 kilometers, so these short-legged birds can't span such a long distance to support Ad-Damazin and Niger Base.
But the Sukhoi Su-27 is a different story altogether. Despite many criticisms, its combat radius is much larger.
Moreover, this is Africa, where overpowering firepower isn't necessary.
The Su-27 armed with two 250-kg cluster bombs and two sets of four Blue Sword Missiles each, plus an auxiliary fuel tank, can fly over, strike, loiter a bit, and then return.
The Chinese pilots now have formal identities as contracted flight instructors of the fighter jet 4S shops. When they'll hold classes depends on how the 4S shops do business.
Before that, though, they need to take turns servicing the two Su-27s to provide long-distance support to Ad-Damazin and Niger.
