On my server rtv voting pops up 10 minutes in and roughly 10 rounds in.
Another issue I have is when maps actually change, I have sm_rtv_changetime set to "2" and it changes the map 15 minutes in, so about 45 minutes out of 60 even though there aren't any map rounds left.
mp_timelimit 60
mp_maxrounds 30
sm_rtv_minplayers "6" - had 4 players in my server and it initiated a map vote (mentioned above, 10 minutes in)
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