So this popped up in my email today.
Destiny 2 PC Is Migrating to a New Platform
You are receiving this email as we've identified your account as an owner of Destiny 2 on Battle.net. Destiny 2 developer and publisher, Bungie, transferred the Destiny 2 service to a new PC platform on October 1, 2019.
Blizzard and Bungie are committed to making this transition as simple and seamless as possible for the Destiny 2 PC community.
This is a final notice that you are still able to migrate your Guardians, gear, game progress, product licenses and Silver currency balance from Battle.net at no cost.
Please note you will lose access to Destiny 2 if you choose not to migrate to the new platform.
For more information, as well as future information and updates from Bungie, please visit
https://www.bungie.net/PCMove.
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So seems that Bungie are moving off Blizzard onto a platform of your choosing(I chose Steam).
