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VVT Cam question

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Road tuning my Audi RS7 with a DS1 and I am trying to determine cam adjustments. Compared to stock I have removed the restricted twin scroll exhaust manifolds, added larger turbine housing, much bigger turbos and an open exhaust. EMAP has been reduced immensely.

The stock tunes have the intake and exhaust cams advanced at low rpm (1000-2500) and low load areas with both cams retarding up to the point that boost comes on (3500) then the intake advances and the exhaust retards heavily to create more overlap (4000-7000).

I have read and watched several articles and videos on VVT cam settings. I have tried different approaches and on the road it’s tough really seeing a difference, but I have noticed that the system will calculate different pressure targets for the same load target with the cams adjusted. I am assuming that adjusting the cams is adjusting the ECUs VE calculations. My questions:

1. Any insight in the cam strategy with lower emap and larger turbos I should consider compared to stock?

2. Any metrics I should focus on with road tuning for the cams?

3. If the system targets a higher pressure at the same load, does that mean the VE has been reduced? Car has determined a higher pressure is needed to hit the same load?

4. All the Cam articles/videos refer to low rpm vs high rpm strategies. What does that really mean? With a turbo car do you use the turbo spool up as the transition point from advance to retarded cams? Is overlap helpful even if EMAP has been reduced? I was surprised to see the intake cam advance so far on the stock setting given so much info says the cams should be retarded for high end power. I assume the high emap and overlap is the reason.

5. What happens to AFR and Timing with or without overlap? If the overlap is good, do I need more or less fuel or more or less timing.

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