Very useful guide! Is it really correct that the hole traffic has to go over 1 site?

I mean: blue data plane goes 1 site and if you want with AS Prepend green data plane goes the other..

Then the statement 100% north/south traffic goes via 1 site is wrong in my opinion, its more like,

all blue traffic has to use the same north/south site and all green traffic has to use same north/south site (if you want the other one with as prepend).

Hint: In this scenario of course you have to use /24 BGP external ip adress blocks for blue and green site.

I dont see the limitation here. Its limited to the green and blue data plane but not to the hole traffic, right?