I'm shopping for some MC2207411-SR4L to upgrade to 56GBE networks, and I need MPO/MTP cables to run between them. I get the difference between A and B cables. A go straight through, B go 1-12 on one end and 12-1 on the other. C swap pairs so 123456789 10 11 12 goes 21436587 10 9 12 11 . What I can't find any reference for anywhere, and I've spent nigh on an hour googling and reading, is when to use which? The plan is to run ONE cable direct between MC2207411-SR4L across the room for validation and testing, with no keystones, no patch panels, no fiber boxes or splitters, and a big spool of unused optical cable sitting on the floor tucked away in the corner. So the over all polarity between two MC2207411-SR4L, is it A, or B? (I'm relatively sure it's not C)