All answers are true, but it also depends on the opportunites & you style of play.
In current GW3, I was looking for bases in Nice & Warsaw since a long time. I had already planned to go there after my fleet renewal. Big bankrupts did happen in both, and my surge there has been very progressive - especially right now in Warsaw, as I'm both replacing aging leased 737s & Ejets, plus replacing my last owned ERJs by Ejets also. After 500 days, I just have 8 planes there. It's a pity, and not very efficient. But by settling there as soon as the other bankrupted, I also played a psychological game to prevent any 3rd guy to come here.
That's not an example to follow. I did that because events didn't match my strategy, and I did decide, in both cases, that events were more important than pre-determined strategy. It's a dangerous game. It worked well in Nice. In Warsaw, not so much. Yet.