LOTRO Community Manager Andy “Frelorn” Cataldo posted a notice on the forums about upcoming server downtime:
The LOTRO Game Servers will be brought down on Wednesday, January 20th from 6:00 AM – 1:00 PM Eastern (-5 GMT) for an update. Patch notes will be available during the downtime. Thanks for your patience, and we’ll see you back in the game soon!
This will likely be Update 17.2.