There are two kinds of people from Twitter that are concerned about losing their handle or posts in a server change:

The first is people who perceive a discontinuity and it makes them uncomfortable. It is a reasonable discomfort but the answer is to tell them to calm down and not worry about it so much it's not that bad.

The second is people for whom this is really bad because they are brand building or have based their entire identity around their posts so this constitutes a painful, unacceptable loss. These people have to go back.