@agu10play for some series (such as Tis Time for Torture Princess, Summer Time Rendering, The Vertical World, etc), they do have the complete list of chapters. And Hokkaido Gal is currently tagged for the same as those - all chapters available.
However, they could decide to limit its chapters once it gets enough to actually have a backlog. They do that for everything in Shonen Jump, but I don't know how they determine it outside of that. So it might happen to Hokkaido Gal, or it might remain all readable.
and I thought there used to be a way to buy "volumes" of the series digitally, but I can't find that option anymore. Maybe they've just decided to let Viz handle the backlogs at their own Shonen Jump app.