From this old FAQ, does this part about Ghost Ships and fog banks still hold true? (for regular fog banks, not those created by smokepot specialists/shot)
Q: If a ship becomes “ghostly” while in a fog bank and is forced to leave the fog bank, where does she exit?
A: She can exit at any point along the edge of the fog bank!
Very interesting read. It’s always neat to see very early versions of things that become much more established later. It’s also a good reminder of how the traditional “Q & A” format for a FAQ becomes horribly unwieldy when it grows beyond a couple pages, or when interactions between rules become more complex than what a few loosely-targeted questions can handle.
As for that particular ruling, it no longer applies. It was intentionally removed at some point, but really wasn’t needed in the first place. Ghostly or not, you use the die roll to establish the ship’s exit point and move from there (which could be right back over the top of the fog bank). The same applies to abilities that ignore terrain while moving.