Pensil A11/P11 for MAOP 11, how to best compensate for bracing?

Got myself a pair of MAOP 11.2's and thinking the Pensil A11/P11 will be a good home for them. Have been ogling Frugal XL's as well but prefer the form factor of the Pencils. I also believe they will have a bit higher WAF :).

Now I want to make these as good as possible, so I am planning to make the panels "Constrained layers" by using 15mm BB ply and gluing on 4mm ply with a thick flexible glue like Tech7 or possibly construction foam. This should add up to panels of 20mm thickness. This should be pretty stiff and have excellent damping of ringing in the panels.

Still I guess bracing like super pensil12 would be a good idea? That's my current plan anyways. So when adding bracing to the Pensil A11 I saw Scott recommend to adjust the internal volume to compensate for the volume of the braces. In that post I saw the suggestion was to move the sidewall(s) out and then compensate the port opening for this movement.
I am assuming that compensation would be to make the area of the port the same as before moving the sidewalls, correct?
My first thought for compensating the volume would be to move the back wall of the speaker, but that may perhaps have other consequences for the tuning that are less desirable?
Intuitively seems like a good idea to move the back, since it will not change baffle size and allow the port size to remain the same, but I don't know how all the dimensions here affect the tuning.
Joined 2001
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If you target the 30-40% holes recommended, you should add two-thirds of that to compensate.

So a 18mm holey driver brace parallel to the walls i push teh sides out 12mm. The vent size needs to be adjusted to maintin the same area.

But as long as the net cross-section area remans the same.

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