The Dark & Light Steam page has been updated to inform the community that servers will be consolidated from 344 official servers to 100 when the consolidation process is complete. The merging process will be completed in two phases. The first round will take place near the end of January to close completely inactive servers. The other will take place in February to consolidate low-population servers so "each server has a healthy population".
In an upcoming patch we will be disabling server transfers to servers that will be closing, which means players will only be able to server transfer to the soon to be remaining 100 official servers. We highly recommend that you do this as soon as possible to avoid any potential issues.
We'll be working closely with our customer support team in order to insure those that do transfer over correct any issues that may happen. Please screenshot of clip your transfer process just in case, and so player support will be able to assist more promptly
Server data from closed realms will be retained and players are urged to contact customer service to "acquire a copy of the data" in order to continue to play on a local or dedicated server.
Read the full notice on the Dark & Light Steam page.