From the OC Register:
Just got word today that the new Monorail Red train will not open to the public this Friday.
Disney Spokesman John McClintock said the team working on the Monorail “has decided to take a few extra days for test and adjust so it will not open to guests on Friday.”
No date has been set for the Monorail’s public launch. We’ll keep you informed on this blog about a public opening date.
According to this blog post by Brady MacDonald at the LATimes, the new Monorail train has been testing since mid-March.