In the latest server game, if you use the city list, set it to sort by population, descending, it yields a list of mixed populations instead.
It does seem to 'change' the list order when you select the sorting parameters, it just doesn't do so correctly.
Thank you for your report. Apologies for not having had time to look into this yet: I have had quite a number of reports to deal with following the release of the most recent major version, and I have had to prioritise other things at present.
I should note that the systems for counting town population are not entirely consistent at present pending the planned full upgrade of the town growth feature, which might at least partly explain this issue (a deprecated measure of town population, no longer used for most display purposes or for passenger generation has to be retained because it is needed to make the old/current town growth system work, pending the overhaul of that system).
No trouble James, we appreciate your efforts.
Sorting by population is the quickest shortcut to find the best passenger routes, that's why I was surprised to see it broken.