Share for Review (InDesign) always asking for user to login

I'm not sure if this is in any way linked to the Publish Online issue, but as of yesterday I've been informed by colleagues that all of my 'anyone can comment' Share for Review links, created within InDesign, are asking people to sign in. The majority of my collegues don't have Adobe IDs and don't wish to create one. Any ideas as to what's happening?