Looks like it did

36.0 / 2.0

internally.

Looks like directly after an inventory unit gets a unit cancel created, it doesn't set the inventory unit as canceled. In my code I was effectively doing:

inventory_units.each do |inventory_unit|
  Spree::UnitCancel.create!(inventory_unit:).adjust!
end

inventory_units.cancelable.each(&:cancel!)

But the solution was:

inventory_units.each do |inventory_unit|
  Spree::UnitCancel.create!(inventory_unit:).adjust!
  inventory_unit.cancel!
end

I wonder if we could make

Spree::UnitCancel

handle that state change itself.