Perhaps you’re right. I was thinking that if this was part of a network of pay phones that they would want to be able to handle more than just the 2 calls per l

Perhaps you’re right. I was thinking that if this was part of a network of pay phones that they would want to be able to handle more than just the 2 calls per line an BRI would allow with less infrastructure (though I think lower rate calls are possible through additional multiplexing)