Paper was accepted for publication 6 months ago without any updates since then, how should I proceed?
Just ask for an update and an estimate of when it might appear. There isn't any special form for that. But &quot;future issue&quot; is pretty nebulous. For a print journal there are issues of finding a proper &quot;fit&quot; for the paper depending on the topic and even the page length.
And yes, you should answer emails. You've been assuming what they should do without verification. Ask. They are unlikely to send you anything if you don't. Just be polite.