So by "hardcoded" is what it actually means just that "you can't avoid them, because you can't have reported your population to the caravan yet as of summer and autumn" ?
In this context, "hardcoded" means it's built into the game itself and you can't change it. No editing of the raws, or the init files, will matter.
I know what hardcoded means, but by that same definition, EVERY other migration wave is hardcoded, isn't it?
Given krenshala's testimony that the second wave can indeed have no dwarves in it, it makes it seem just the same as any other migration.
So yes, they would still be hardcoded. But so would the other infinitely many waves after them, to the same standard (i.e., even if you've reached your cap or are a horrible fortress, it will still check each time, just like the first two times).
I was led to believe that the first two waves are "special" insofar as you get dwarves no matter what, despite anything you do. But krenshala is saying that didn't happen for him - huge amoutns of death did indeed make the second wave have zero dwarves. So I'm left with nothing else to interpret them as "special" by.
I'm not aware of any raw or init file changes that will completely turn off any migration wave, be it the 2nd or the 37th. All you can do is change the pop_cap, which doesn't prove anything, because it requires the liaison to report back, which hasn't happened yet by the 2nd wave.
In order to know if they are indeed "special" in any way, you'd have to hack in a liaison report in the first week or whatever that wouldn't normally be possible, while also having a pop cap lower than 8, and then see if the migrants still came in the first two waves. If they did, then that would be an indication of the first two waves being special somehow.