Update: 9:27 am PST: The backlog has been worked through and message delivery has returned to normal.
This morning (January 13th) from 6:00-7:00 am PST message delivery from Yahoo! Groups was down, and we are still experiencing delays as our systems work through the backlog of messages. We apologize for any inconvenience this has caused.
- Yahoo! Groups Team
P.S. This problem only affected email message delivery. If you are experiencing any other problems, it is unrelated to this issue. Please contact Customer Care if the problem persists.