The move makes sense.
Riolacci, the current Group CFO had announced his 4 November departure early July. So they needed a replacement. Gagey is a financier, so that's a good fit. But it is clearly a demotion ans whether he will stay there is an open question.
Having Janaillac become PDG (Chairman and CEO) of AF makes sense and it will be interesting to see who is appointed effective CEO.

The article states that AF finally got profitable in 2015 after years of loss. AFKL did show a small net profit in 2015 (118 million) after many, many years of loss. I don't know it it was also the case for AF alone.

Anyhow, 2016 is looking bleak for AFKL. The first semester showed a net loss. Q3 2015 showed a great profit (480 million) last year and that generated an annual profit of 118 million. However, the traffic figures released lately for the third quarter 2016 are not good and the Q3 2016 profit figures to be released this week might be less good. Q3 is usually a good profitable quarter.