Modify instances in an existing linear pattern

I cannot figure out how to do this:

Here is an example:

I have some existing linear patterns of some holes in a pipe.

I want to be able to vary the distance of certain "instances" of these holes.

I know I can do this in the feature manager, but I need to be able to do this using the API.

I found this excellent Solidworks article on how to "Create a linear pattern" from scratch and assign different spacing to specific instances.

The problem is that I am using complex parts with several linear patterns already created that have feature driven patterns relying on them.

I do not want to have to create these linear patterns and feature-driven patterns from scratch when I already have them created and set up.

I just cannot figure out how to "Modify the spacing" or "Skip instances" for these existing linear patterns using the API.

Solidworks picture I sent to message board question I asked about how to skip instances and change spacing in linear patterns.png

Any help would be greatly appreciated

Thanks