Someone from Steemit Inc. should answer this question as to why it's no longer alphabetical, but it now appears to be somewhat in the order of when we followed or when we were followed.
The exceptions to that might be if you unfollow and then come back and re-follow them, they seem to go back to the same point they were to begin. This is all based on observations I made with my own account after seeing this question, but I do believe it to be accurate within that context.
I'm not sure what the advantages would be to having them in this new order, other than to more rapidly see, if one cares about such things, whether or not someone you recently followed decided to follow you. Since I don't follow with that intent, it's not a great concern.
I don't spend a whole lot of time looking at either list, so thank you for asking this question. I could have gone several more days, if not weeks, without realizing any changes took place. Steemit Inc. has been a little more communicative over the last year, but when it comes to UI changes, they don't normally announce them, and we're left discovering them afterward, and in some cases, scratching our heads as to why this or that was changed.