I knew 1 Foreign 320 TRE who was offered 330 at X. As they are different Companies even though under the Group umbrella he had to be terminated from Air Asia and reemployed by Air Asia X.
That is to do with Immigration and Work permit issue. It also meant his Bond was cancelled with Air Asia so he left to somewhere else before signing up with X. That was a while ago though. I suspect they learn t from that.