Monthly Rivals

I am new to Forza and as a competitive player I really enjoy the rival mode but I have some questions about those monthly events. When do they end exactly? There is no information about this ingame. The events that were there at launch are still there now in October, so it’s obviously not simply the calendar month. I think the end date should be displayed ingame together with the car restriction.

Also what happens when a monthly rival event is over? Does it disappear from the game or does it just get locked but stay there, so that we can view the final leaderboard? Maybe some people who know Monthly Rivals from previous Forza games can share how it worked there.

Seeing as the game didnt officially launch till the 27th of September you would expect them to be there till near the end of October as well
From what i remember in previous games they just disappear never to be seen or heard from again
Sometimes there was an option to see closed and precious events though