Just going to add a side note. I probably wouldn't have lumped these back under variety. Silphiums are likely to be split out more rather than lumped back in, in future. I do understand that it follows POWO, and honestly there's not a satisfying Silphium treatment (Mason Brock's treatment in Flora of the Southeastern US is the best I've used and even he admits it's not perfect). For now this is probably the logical step, but I expect this may be undone in a few years.
Identification
ID 2 of taxon E will be an unintended disagreement with ID 1 of taxon B after the taxon swap
If thinning a parent results in more than 10 unintended disagreements, you
should split the parent after swapping the child to replace existing IDs
of the parent (B) with IDs that don't disagree.
Just going to add a side note. I probably wouldn't have lumped these back under variety. Silphiums are likely to be split out more rather than lumped back in, in future. I do understand that it follows POWO, and honestly there's not a satisfying Silphium treatment (Mason Brock's treatment in Flora of the Southeastern US is the best I've used and even he admits it's not perfect). For now this is probably the logical step, but I expect this may be undone in a few years.