When zooming past a certain level around NZCH, the view is abruptly panned far far away from the current view. Wild guess, the 180th meridian could well be a factor in this bug.
Steps to recreate: Mercator projection.
Create flightplan NTAA dct NZCH → Click button to see entire route (if not already shown) → Start mouse scrolling with the cursor over NZCH, to zoom in → When passing 30NM scale range, view is thrown over to Australia.