Moving from attachment to core upload

Hi,
As attachment will not be continued in 5.0 version of drupal, I do plan on moving to core upload system, even if this module lacks some features, such as a way to prevent the bug if two people try to submit two files with the same name.

So now I need advice on how to migrate my existing nodes from old attachment system to core upload one. Should I take all my nodes one at a time and upload the same file, then delete the file from attachment system? Or is there an easier way to do this?

Thanks