If you have your Covenant Hearthstone set to your Covenant Sanctum and swap covenants in Patch 9.2, your Hearthstone will automatically update to your new Covenant Sanctum! As mentioned by Jdotb, a new quality of life change has been made to Hearthstones in Patch 9.2. When you swap your Covenant, if your Hearthstone is set to a Covenant Sanctum, then the destination of your Hearthstone will automatically swap to your new Covenant Sanctum, instead of changing to the Ring of Fates.
As you can see in the video below, if you are a Night Fae player with a Hearthstone set to the Heart of the Forest and change to Kyrian, your Hearthstone will automatically update to Elysian Hold! This can be very useful for returning to your Covenant Sanctum to change Conduits or pick up Callings, but don't forget that Zereth Mortis has a Forge of Bonds as well.
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