Roof flashing, tricky slope transition inside corner – GreenBuildingAdvisor

I’m doing my first standing seam roof on our forever home and have a bit of a head scratching flashing detail I can’t figure out how best to deal with.  Trying to do best practices so going the extra mile with hooked panel ends and closing off the ribs at the end etc.

It’s an inside corner at a slope transition (2:12 lower, 4:12 upper).   I have to install the lower course first, i haven’t started the upper course yet so not exactly sure where the upper panels will lie, but regardless I think i’m dealing with some variation of what’s shown in the photos.    A section of roofing that isnt’ going to plane out at the slope intersection, also leaving a triangular gap under the slope flashing.

I haven’t been able to find any examples on the intertubes how to deal with this, so wondering if any more experienced builders could provide some suggestions.

My initial thought is to install a smaller sheet cut to fit around the intersection at start of the the slope transisiton for the upper course to lap over, then perhaps run the slope transition flashing long and cut/fold/seal to close off that triangular gap ?

Any suggestions would be really appreciated.  Thanks kindly,

David