>>150030754
The only problem here is that goose seems to imply that the way this main story ends leaves not much to expand further, which could mean 'everyone fucking dies' (doubtful) or 'we reach a true state of stagnation where it's impossible to move forward/grow and we cannot turn back either' (idk how that could go desu).

If glitch decided to make a prequel or something to explore the lives of characters long gone or whatever the deal with C&A is it would all be unsatisfying because depending on the end it would all amount to nothing. If they decided make a sequel or follow up there would have to be some retconning or stepping back from already established character developments we've seen so far. Also it does not help that the series so far seems to take place within the first week(s?) of Pomni arriving, there isn't much to explore in extra filler episodes taking place within that timeframe when the main plot is more appealing anyway.
Maybe there would be some small gag comics like the mange seems to do but otherwise I don't see much expansion once the show is over