Most pairs in the Yi are reflections of each other. Like a mountain in a lake: upside down.
Another combination is the 'contrast': every yang line in one hex is a yin line in the other and every yin line is a yang line.
When you cast hex.5, the Yi gives advice. But 6 does have some meaning in the advice as well. It is the view from the other side. Not advice about what you should do, but sometimes it is helpful to see "the other perspective".
The top is now at the bottom, the bottom at the top. Line 5.1 becomes 6.6, and so on. Line 5.5 is about relaxed waiting. Its reflection, 6.2, is also about not being able to do what you want to do, but this time it is not relaxed.
Hex.5 line 5 changes to hex.11, hex.6 line 6 changes to 12, which is - of course - the reflection of 11, because that is how it works.
Between 5.5 and 6.2 is a reflection. For hexagrams and for lines it works the same. In hex.5 there is something you need, but you cannot (yet) get it, so you have to wait - or leave if you are in the wrong place.
In hex.6 there is something you need, but you cannot (yet) get it, so you have to fight for it - or refrain from fighting if a fight makes no sense.
Waiting for it or fighting for it - two sides of a similar dilemma. In hex.5 the solution has to come from the outside, you have to wait. In 6 it has to come from you, you decide if you are going to fight and you are the one fighting.