Yes, once the BackerKit surveys are sent out you'll be able to purchase add-ons a la carte on that platform, including previous issues.
We have eight issues total planned, split into two arcs. Issue #4 marks the end of the first arc as well as the midway point of the story.
About once a year. We've gotten faster at pumping out pages, but our issues have also grown in length over time.
Yes, it's one of our long term goals. Right now though we need to raise funds to continue production of the series.
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