i don't think he'll say it, and even less in a public comment, i mean, knowing it already would break the interesting part of the scene/plot
well, can't blame you to be curious, the plot is realy interesting for an adult game, with a relatively heavy atmosphere, so wanting to know more or less how it'll end in normal
though, maybe there will be multiple ending, and so on the anwser of your question will depend of the choice you're doing in game x)
it wasn't the case for the last content with Sakyua, but early we already had some choices that impacted how thing turned out after, so exept if they are dropping the idéa of a kind of visual novel with different routes/choices for a fully one route visual novel, i don't think there is a definite/precise/unique anwser to your question
well, i'm not them, don't take everything i just wrote for granted, it's just my speculation and maybe he'll give you an anwser x)
PS: why does it have to end with an uphill rollercoaster too ? xd tought it is of course how people hope it'll end x)