The Twitter service continued to be patchy hours after the firm said it would be down last night due to a failed upgrade.
The site was taken down at 8pm PDT on Monday night and was due to be up and running again at 3am, but was still reporting capacity and other problems hours after that.
At 6.15am UK time, the Twitter status blog said, "Users may temporarily experience missing tweets from their timelines. They will be restored shortly."
But an hour later, an update said, "We're recovering from the site outage. Remember, users may temporarily experience missing or duplicate tweets from their timelines. Normal timelines will be restored shortly."
Earlier notices said the problems were caused by a failed enhancement of a new approach to timeline caching.