Sqlpackage.exe writes warnings to std error

After updating from 1.3 to 1.4 I am having a problem with a powershell script that runs sqlpackage command. In the web interface I get

"INFO ERROR: *** object [DBUser] already exists in database with a different definition and will not be altered."

message from sqlpackage. and a line

DEBUG Script 'xxx\PostDeploy.ps1' completed with return code -12.

When I run this same script using tentacle on the server I get

@@@
Running PowerShell script…

PowerShell exit code: 0
Output:

@@@

So I am not sure where to find the error. I have tried redirecting the std error on the call to sqlpacakge but it did not fix the issue either. I also do not get the "Error: " output when running it manually.