New Post: Reprojection Inaccuracy from 20355 to 4326

I am trying to reproject some points in EPSG:20355 to EPSG:4326 and cannot seem to get an accurate result.

Here is an example:

Point in EPSG:20355: 665423.2146,7458565.1391

If I reproject this point using the http://epsg.io/ website I get the following result

148.6147785 -22.9713145

If i reproject the point using ProjNet I get the same result

However when i reproject the point using DotSpatial I get a different result
148.613698385575 -22.9728720945436

Here is my sample code:

var sourceProjection = ProjectionInfo.FromAuthorityCode("EPSG", 20355);
var targetProjection = ProjectionInfo.FromAuthorityCode("EPSG", 4326);

double[] fromPoint = new double[] { 665423.2146, 7458565.1391 };

Reproject.ReprojectPoints(fromPoint, null, sourceProjection, targetProjection, 0, 1);

I have tried creating my source and target projections from Esri strings and Proj4 strings and always seem to end up with the same result.

Any guidance as to how I can get an accurate result would be much appreciated!