Complex sentence: It's not about the number of references-there are no special circumstances here which mean we should not follow which says "Until the start of principal photography, information on the film might be included in articles about its subject material, if available".
Split into simpler sentences: It's not about the number of references-there are no special circumstances here. There's not reason not to follow which says "Until the start of principal photography, information on the film might be included in articles about its subject material, if available".