Mcnasty Normally, planes only come in on different paths if the target is equidistant from two edges - on that imaginary line that splits the map top to bottom or left to right. In that case, it is random which edge they come from, they could all be together or split in any subset. In your picture, it is clear they are not equidistant from the edges with the new forest added, but it looks like they might be equidistant from the old edge line. Yet another confirmation of the issue
MartinK12 reported and documented in his picture.