3" drain with horizontal branches, WC limit

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las vegas, nv
My project is governed by the 2012 UPC. Single story house, 3" drain pipes. To help visualize my drains, think of my layout as a 3 pronged fork. The handle and center tine are the main drain, and there are two horizontal branch drains represented by the the left and right tines. The main drain has a WC connected and each horizontal branch drain has a WC.

I am using Chapter 7 of UPC for reference, not Appendix C.

As I read table 703.2 footnote 4 regarding 3in pipe it states "Only four water closets or six-unit traps allowed on a vertical pipe or stack; and not to exceed three water closets or six-unit traps on a horizontal branch or drain."

Since two of the WC are on their own horizontal branches can I add another 2 WC to one of the horizontal branches? In other words, if the WC is on a horizontal branch is it considered connected to the main drain as far as footnote 2?

If so, then in theory as long as the total DFUs don't exceed 35, then could you have 3 horizontal branch drains each with 3 WC, so totaling 9 WCs?

I've looked at Appendix C, but there I seem to be out of luck as Table C5.4 footnote 2 limits the number of WC on a horizontal branch to be 2.

My house is part of a large development, where they have my model and a second version with identical first floor plus a second floor which has 2 more bathrooms. I looked at the plumbing blueprints at the county and they showed 3" drains even for the two story model which would have 5 WC total.
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