Ingress movement - Horizontal Movement (beyond the range 1 placement)

[carnage4u]

I've been seeing people use horizontal stairs or narrow ramp as ingress points.  These usually involve stairs that are too narrow for a model to fit on, so they are declared ingress points.  They are high enough to go to a second level (a height higher then range 2). They are vertical, but also horizontal and often give 2 to 5 more inches of horizontal movement.  This is before factoring in the range 1 placement of putting a model down after using an ingress point.

The rules talk about ingress points being for vertical movement and placing within range 1, but don't call out scenario of gaining additional horizonal range beyond that.   Wondering if this is considered within the rules.  A lot of decisions i may make on buying terrain can be impacted by this decision.

[Thoras]

Ingress points should be discussed between both players prior to the start of the game and with the understanding of the movement options they provide to characters.

As long as both players agree to it, nothing in the rules prevents players from defining Ingress Points separated by horizontal distances as connected Ingress Points.