Hi Wilhelm,
Thanks for posting!
I can't see any way to do this without creating an individual resource for each possible combination between A and B tests, which I presume is something that's occurred to you but is considered not an option because it's very messy and hard to maintain.
Can you describe a bit more about the nature of these tests and the reasoning behind their constraints? It sound as though the concurrency constraints don't seem to be tied to specific resources, so I'd really like to learn a bit more about this use case.
Cheers,
Remco