Option to sort users in UI Kit UserPicker dropdown


I’ve got an app that makes use of the UI Kit UserPicker module and a customer has asked if it would be possible for the displayed users in the selection dropdown to be shown in alphabetical order. At the moment the users seem to shown in random order (as far as I can tell).
Obviously ordering doesn’t matter so much when you are searching for a particular user but in this case they want to be able to select every user one at a time and it is hard to keep track of where you are when the list of users isn’t sorted at all.
Also as there doesn’t seem to be a way of getting all Users for a Confluence instance, I can’t get a sorted list of users to put into a standard Select component as a workaround.