Thank you for looking in to this I will await a final clarification on the matter.
In the meantime, I manually filled out paper worksheets using both scenarios .
SCENARIO 1: Just using LINE 10 as my input.
SCENARIO 2: Combining LINE 9 and 10 as turbo is currently doing.
In my particular case , it had no effect on the end result. However it may affect others.
Looking forward to a final determination on this from Turbo.
