If 180 is just to the right of center screen (displayed as 180 E) then track lines stop at 180 and only points appear farther East.
![Image](http://livinginparadise.info/VR/images/180E.png)
Conversely if 180 is just to the left of center screen (displayed as 180 W) only the track lines east of 180 are shown.
![Image](http://livinginparadise.info/VR/images/180W.png)
It's not really a big deal unless you are following boats on both sides of 180.
Anyway, just thought I'd give you a "heads-up" in case you weren't aware of it.