[UPDATE] It looks like servers have been brought online as per the following Tweets
"The game worlds have reopened. We will be monitoring the health of the game world overnight, and will provide more information about a thank you gift and other matters in the near future. #LOTRO 1/2. Please note that most in-game chat and Friend/Ignore lists are disabled except for /say and /tell. We will let you know when our world chat service reopens. #LOTRO 2/2"
Standing Stone Games brought down all of the game worlds in The Lord of the Rings Online yesterday, and as of this morning the servers remain offline. This continues over a week of instability and downtime that has marred the end of the Midsummer Festival in Middle-earth.
The LOTRO game worlds remain down while we work to resolve issues at our data center and related environments. We will keep you updated. We will have more information about timing of events, sales, subscriptions, and more in the near future. #LOTRO— LOTRO (@lotro) July 23, 2020
The past week has seen servers down almost altogether (RIP Arkenstone), while others have been accessible, they've been far from playable. It feels like this time the team at SSG have simply opted to bring everything down to get to the crux of the issue at their data center that is causing the instability throughout Middle-earth.
Having come at the tail end of the Midsummer Festival, as well as player-run events like the Annual Weatherstock festival on Landroval, the team is promising more info related to its events, sales, and most importantly those who are literally paying for this downtime with their subscriptions. When players will hear remains to be seen, with the team simply stating "in the near future."
Hopefully this extended downtime can allow the team to find out what is causing the instability and ensure it doesn't keep happening when they re-open the game worlds. We'll update this story as more information becomes available.