I usually spawn standard servers and as you know you cant enable all maps for standard servers . When I try to change map in game (call vote) I see all quake live maps on that page.
My suggestion is ; developers should remove unavailable maps from call vote screen so people can see which maps they can vote and don't waste time trying figure out which maps are available.
(Premium servers has same problem too. You cant enable all maps due to map number restriction, so some of them still become unavailable.)
Sorry for my English , Have Fun.