Divide along creases? Extract isocurve?

I have a surface with a crease that is crossing a line I want to split along. I’m getting some problems at the intersection of the crease and the split line. i.e. naked edges when trying to close it up for volume measurement farther down the road.

I thought I’d try to divide the creased surface into its two planes and split them as individuals… However an obvious way to do that doesn’t seem to be jumping out at me.

Ideal solution replicates the effect of DivideAlongCreases in Rhino where I don’t need to pick anything… Just input a surface and output a list of trimmed surfaces.

or Extract Isocurve and split type solution could also work however that wouldn’t be as flexible in terms of geometry input rules.

Hi @wynott, could you provide an example file with before and after state ?
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c.