There was an article on the Beeb mentioning that people were asking for it to be delayed til Summer because of health concerns but I don't know if that's the thinking behind it.
https://www.bbc.co.uk/news/entertainment-arts-51720354
I’m seeing other articles online blaming Coronavirus for it, which makes sense. Why watch a $250m movie flop because people don’t want to catch germs in the cinema?