What is wrong with unofficial expansion? Do you want to change the description just because of those few guys on aokheaven, who complain about it? it is clearly an expansion and it is unofficial. Thats all.
+1 This is being overanalyzed way too much. If some wanna call it a mod, fine with them. If some wanna call it an expansion, good for them. It's just a another game in the end. But I can understand why the admin for this forum feels strongly about this topic.