Haven't been there for years.... used to just have a forecast for my selected location, now it has 3 or more.... WTF?

What is GFS, ICON, NNW3 50KM (50km to the NNW of my location?), GWAM 27km?

What huh?

Same happened here in se-qld a few years back. Even got the names right

I find it the best of the lot for predicting the local wind and rain

I think they are different weather models.
As we know Mother Nature can be as complicated as she is beautiful. Different peeps have developed different sets of models. The beaureau, and the private weather forecast suppliers tap in to or purchase one or many of these forecast models. Each model has strengths and weaknesses and the provider can choose the most appropriate, or show you the options.....
OR. I could have just made that up after a bottle of red...

They would be different weather models.

The km are probably the grid size of the model used. Kind of the resolution of the model.