The OP (Nick-H) was trying to resolve an issue regarding bibliography sorting based on order of appearance for an author with multiple publications while maintaining the bibliography list in ascending alpha order by author name. Changing the bibliography sort order to “order of appearance” alone won’t address keeping the author names in alpha order.
It seems to me the second poster (ioannis) wants to do the same as the OP but is using a numbered style. However, even taking that possibility into account doesn’t sufficiently explain what the user is trying to do. So, ioannis, could you provide further description and perhaps examples?