Thank you for contacting Intel community.
For your information 10M16DCF484C8G is still active and available. Anyhow, the life cycle is depending on its order volume. Hence, we do not have the estimated EOL.
You can subscribe to our customer notification mailing list at below link so that you can be notified when an Altera(now Intel) device is going to be discontinued.
However, a lifecycle of a new device (eg: Max 10) should be about 10-15 years depending on its ordering volume.