Beginning and ending degrees of Moon nodes--transit and natal...

I would like clarification on the degrees as it applies to the Moon nodes. Its my understanding when planets are at 0 degrees it's about beginnings. At 29--culminations and endings. However with Moon nodes that are mostly retrograde in motion--does this rule still apply?

It's a little confusing in a way because as nodes enter a new sign at 29 degrees--the theme of its transit (or in a natal chart etc) is only starting isn't it? And as it enters 0 degrees, its ending... How do we interpret this?

I assume then the same rule applies for planetary nodes, right?

Thanks in advance