Could the Nikon 400mm 2.8 be something for you? Because you wrote you couldn’t decide between 400 & 600. You would nearly cover both lenses inside one.

And how long do you need for processing mid game? I presume you shoot JPGs? So how does your editing look mid game and after game?

Is it even possible to calibrate an iPad? I’ve read that the iPad Pro 12.9 M2 had the reference mode where you can set your display to various colour spaces, including sRGB. But AFAIK you have to calibrate your monitor from time to time because it changes over time. I don’t know if you are able to do this with an iPad.

But AFAIK the sRGB lays inside the P3 and P3 only extends some colours. Please correct me on this if I’m wrong.