I can't find the answer to this one anywhere. Related Entries appears to be an orderable list within the CMS but using GetRelatedEntries() returns an IEnumerable which of course is unordered. Is there a way I can find out the order of these that appears within commerce?
Which GetRelatedEntries method are you refering to? :) Are you talking about relations/associations for catalog content?
Edit: Found it! I assume you're doing it on the content itself via (EntryContentBaseExtensions.GetRelatedEntries(this EntryContentBase entry)). That will give you the Associations of that catalog content. I would probably recommend using IAssociationsRepository instead, as the Association object has a SortOrder you can use to order the items.
Thanks that fixed it! :)
EntryContentBaseExtensions.GetRelatedEntries should probably return the links sorted by the sortorder of the associations, much like ProductContentExtensions.GetVariants etc does for relations. I'll log a bug for it.
Fixed in Commerce 10.8.1!