Structure block will not allow me to change mode from '3D export' to 'load'

Hi,

I've used the structure block to successfully save a structure as a .glb file, however, whenever I select 'mode' to attempt to load the structure (either in the world it was created or a new one), the drop down menu only shows '3D export' as an option. 

As far as I was aware (from: https://www.minecraft.net/en-us/article/get-some-structure--blocks--your-life), there should be a load and save, as well as export.

If there's a way to resolve this so that structures can be loaded as well as exported, it would be very much appreciated!

Kind regards!