Extend/Recede Polylines by points

Hi Everyone,

I am a beginner to Grasshopper, I have been working on a tower. The Floor plates are made using Polylines connected to points. I would like to achieve the following:

• The floor plates Cantilever on one side of the tower, the plates would increase by increments of 0.300 towards the top.

• The plates would only extend/recede from two specific points (please see attached image)

• For the floor plates above the ‘Cantilever plates,’ the plates would recede by increments of 0.870.

I have split the floors into groups, Regular Plates, Cantilever Plates, & Receding Plates.

With help from this forum, I was able to achieve this with a regular rectangle component but having a bit of trouble using Polylines. Just wanting to know if it would be possible to achieve the above, ideally using a slider or a list. I have attached a reference image and my definition below.

Would be grateful if anyone could point me in the right direction,

Thanks