Tweets from people I'm following don't show up on my home or on 'with friends'

Why does my 'with others' feed have a big gap in updates from everybody I am following? The updates from people I'm following stopped appearing on my homepage (and my 'with friends' page) from the morning of March 28 and only now, several days later, the first new tweet just appeared a few minutes ago. During that time there were 20 or more updates from the people I was following, and none of those show up for me on the site, or in twhirl.
 
sad I’m annoyed
Inappropriate?
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