In the status screen it should show you the convergence level.  You may have to push it a few times to get to the status you want.  There is a setting that allows you to steer at a certain level of convergence.  Once you are below the setting it says converged, but is not necessarily the best it can be.

With centerpoint I have had your problem happen once or twice, because it had not fully converged yet.

I believe Dave meant to move the antenna offset it the settings part.

I've heard it said that if you terrain module is showing a large offset after calibration, that is helps to remount is so that the calibration offset is only 1-2 degrees.  Also make sure the setting for the plug direction for the t3 plugs are facing the way is.