You will need to be on RoomOS 11 - there should be an option to switch from the current RoomOS 10 software train to the new RoomOS 11 train in your Webex Control Hub. If you are using the endpoints as on-prem registered (not registered to the Webex Cloud), this isn't yet possible.
But to answer your specific questions:
1: Miracast is a selectable option right now - Airplay will be "Soon" - you won't get anyone committing in a public forum to an exact date until the feature is available.
2: Similar to 1 - you won't get any confirmation on Roadmap items until they are officially announced - but see note regarding RoomOS software above.
3: Yes, the update will make the feature available when it is released for no additional cost on top of your existing Webex costs.
Wayne
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