So, would this URL be correct always (so, even when the article has no version)? Or are there exceptions?
Would you kindly also explain the difference between the article ID and the publication ID?
Regarding your question about article ID vs. publication ID, one of our team wrote an explanation on publication IDs vs. article IDs/submission IDs ( submission_id and article_id are the same) that might help (in short, publication_id is used for versions):