I would think that it is not possible. Scoreboard changes when someone joins, in my opinion this should trigger the mentioned event.
Maybe I should do something with that:
https://wow.gamepedia.com/API_Reques...fieldScoreData
Lua Code:
RequestBattlefieldScoreData()
Should request new score data from the server and trigger the event.
But I really dont like to call this function from a timer.
Maybe someone knows how to deal with that a better way? All the other addons I have found so far which are doing something similar to what im doing are using the UPDATE_BATTLEFIELD_SCORE event too.
But I think this is already the solution. To periodically call RequestBattlefieldScoreData()