This is an interesting question. In library catalogs and similar contexts, "初～中" tends to be treated as a variant of "初・中" (or vice versa), and assigned the pronunciation "しょちゅう". I assume the same applies for other non-numeric ranges. But I'm not sure if this is the result of a conscious decision by a human being, or just software limitations.
I recall reading that "～" should only be pronounced から when it is either explicitly paired with まで (e.g. "月曜日～水曜日まで") or, less ideally, not paired with anything at all (i.e. just meaning "From X [to an unspecified end point]"). In other cases, including when it is part of a pair that does not have まで after the second item, the rule was that it should not be pronounced at all -- as described in my first paragraph.
This is sort of like the pronounced hyphen in "4-6 mL" ("four to six milliliters") versus the unpronounced hyphen in English phrases like "the Boston-New York route", I guess. On the other hand, I don't remember exactly where I read this tidbit, but it was definitely in a prescriptive style guide so it could be an artificial rule with no basis in actual spoken Japanese.