In my concerns, I've well the balls in the trousers, but know nothing in UK stuff and so I can't help you
It's not because it's commercial it wasn't used by troops. For me it can be issued because of the black tape on the straps... ;
It's often made for a long-time use...it avoids change the size when everything's perfect, when it fits perfectly with the rest of stuff...Sorry, can't explain it better, my english is too poor thatfor...
But again, we don't know the origin of this stuff, and so eveybody can put black tape on it...including an airsofter ! A+ is no more a reference, and sand neither. So we can never be 100% sure it was issued. But that changes nothing, it's still an interesting item...moreover for the price you paid !